Knee joint prosthesis system and method for implantation

ABSTRACT

A method for preparing at least a first bone for receiving a prosthesis can include positioning an IM member in a bone. A scaffold, skeleton or frame can be located onto the bone at a desired location. An alignment assembly can be coupled to the frame. The alignment assembly can be moved relative to the IM member to position the frame at a desired location relative to the bone. The frame can be fixed to the bone at the desired location. A cavity can be reamed into the bone using at least a portion of the alignment assembly as a guide. The alignment assembly can be removed from the frame. A cutting block can be coupled to the first attachment portion. Cuts can be prepared in the bone using the cutting block as a guide.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Ser. No. 11/972,359,filed Jan. 10, 2008 and claims the benefit of U.S. ProvisionalApplication No. 60/978,949, filed on Oct. 10, 2007. The disclosures ofthe above applications are incorporated herein by reference.

FIELD

The present disclosure relates generally to knee joint prostheses andmore particularly to various tibial and femoral components and modularaugments for cooperating with such tibial and femoral components.

BACKGROUND

A knee joint prosthesis typically comprises a femoral component and atibial component. The femoral component and tibial component aredesigned to be surgically attached to the distal end of the femur andthe proximal end of the tibia, respectively. The femoral component isfurther designed to cooperate with the tibial component in simulatingthe articulating motion of an anatomical knee joint. Such knee jointprostheses are generally referred to as primary knee prostheses.

Knee joint prostheses, in combination with ligaments and muscles,attempt to duplicate natural knee motion as well as absorb and controlforces generated during the range of flexion. In some instances however,it may be necessary to replace an existing prosthesis. Such replacementprostheses are generally referred to as revision knee prostheses.Depending on the degree of damage or deterioration of the primary kneeprosthesis, knee tendons and ligaments, however, it may be necessary fora revision knee joint prosthesis to eliminate one or more of thesemotions in order to provide adequate stability. In this way, it may bedesirable to provide a cruciate retaining (CR) revision knee, a fullyconstrained revision knee, a posterior stabilized (PS) revision knee ora hinged revision knee for example. Furthermore, in some instances itmay be necessary to account for bone loss in areas adjacent to such kneejoint prostheses.

SUMMARY

A method for preparing at least a first bone for receiving a prosthesiscan include positioning an IM member in a bone. A scaffold, skeleton orframe can be located onto the bone at a desired location. An alignmentassembly can be coupled to the frame. The alignment assembly can bemoved relative to the IM member to position the frame at a desiredlocation relative to the bone. The frame can be fixed to the bone at thedesired location. A cavity can be reamed into the bone using at least aportion of the alignment assembly as a guide. The alignment assembly canbe removed from the frame. A cutting block can be coupled to the firstattachment portion. Cuts can be prepared in the bone using the cuttingblock as a guide.

According to other features, the cutting block can be removed from theframe. A posterior stabilized (PS) box guide assembly can be coupled tothe first attachment portion. PS box cuts can be prepared on the boneusing the PS box guide assembly as a guide. A posterior foot can becoupled to a second attachment portion on the frame. A joint lineassociated with the bone can be located by referencing a position of theposterior foot.

According to additional features, the alignment assembly comprises analignment member and a locating bushing. The alignment member caninclude a receiving portion. Moving the alignment assembly can includepositioning the locating bushing into the receiving portion, thelocating bushing defining a bore configured to accept the IM reamertherethrough. Moving the alignment assembly relative to the IM reamercan include rotating the locating bushing within the receiving portionuntil the frame locates at the desired location relative to the bone.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is an anterior view illustration of a knee joint prosthesisincluding a modular tibial component having a first adapter assembly forproviding a first predetermined offset according to the presentteachings;

FIG. 2 is an exploded view of the modular tibial component of FIG. 1;

FIG. 3A is an anterior view of the tibial component of FIG. 1;

FIG. 3B is an anterior view of a tibial component according toadditional features;

FIG. 3C is a perspective view of a tibial component according toadditional features;

FIG. 3D is a perspective view of a tibial component according toadditional features;

FIG. 4 is a view of a first adapter body according to the presentteachings;

FIG. 5 is a view of another adapter body according to additionalfeatures;

FIG. 6 is a view of an exemplary stem and fastener insert;

FIG. 7A is a cross-sectional view taken along a superior/inferior linethrough the adapter of FIG. 1;

FIG. 7B is a view of the knee joint prosthesis of FIG. 1 illustratingvarious offsets;

FIG. 7C is an exploded view of a locking assembly shown in FIG. 7A;

FIG. 8 is an anterior view of an exemplary femoral component accordingto the present teachings and shown with the adapter assembly of FIG. 1;

FIG. 9 is a perspective view of a tibial tray and bearing according toadditional features;

FIG. 10 is a perspective view of the tibial tray of FIG. 9;

FIG. 11 is a perspective view of an inferior surface of the bearing ofFIG. 9;

FIG. 12 is a perspective view of a superior surface of the bearing ofFIG. 9;

FIG. 13 is a top view of the tibial tray and bearing of FIG. 9;

FIG. 14 is a cross-sectional view taken along the line 14-14 of FIG. 13;

FIG. 15 is a perspective view of a hinged knee joint prosthesisaccording to additional features;

FIG. 16A is a cross-sectional view taken along the line 16-16 of FIG. 15and shown with the femoral component rotated;

FIG. 16B is a cross-sectional view of a hinged knee prosthesis accordingto additional features;

FIGS. 17-20 show an exemplary sequence of assembling the knee jointprosthesis of FIG. 15;

FIG. 21 is a perspective view of a first augment according to thepresent teachings;

FIG. 22 is a perspective view of a second augment according to thepresent teachings;

FIG. 23A is a plan view of the first and second augments of FIGS. 21 and22;

FIG. 23B is side view of the first and second augments in an mated orinterlocked position;

FIG. 24 is a perspective view of a third augment according to thepresent teachings;

FIG. 25 is a top view of the third augment of FIG. 24;

FIG. 26 is an anterior view of the femoral component of FIG. 8 shownwith the first augment assembled on a superiorly extending portion;

FIG. 27 is an anterior view of the femoral component of FIG. 8 shownwith the first and second augments assembled on a superiorly extendingportion;

FIG. 28 is a superior view of the femoral component of FIG. 27 and shownwith the augment of FIG. 24 secured to an inferiorly extending portion;

FIG. 29 is an anterior view of the tibial component of FIG. 1 shown withthe first and second augments assembled on an inferiorly extendingportion and without the adapter assembly;

FIG. 30 is an anterior view of the tibial component of FIG. 1 shown withthe third augment assembled on the inferiorly extending portion;

FIG. 31 is an exploded view of a modular tibial component according toadditional features;

FIG. 32 is a perspective view of an augment according to additionalfeatures;

FIG. 33 is a perspective view of another augment according to thepresent teachings;

FIG. 34 is an exploded perspective view of an adapter assembly accordingto additional features and shown with an exemplary tibial component andstem;

FIG. 35 is an anterior view of the prosthesis illustrated in FIG. 34;

FIG. 36A is a detail exploded view of the tibial tray and adapterillustrated in FIG. 34;

FIG. 36B is a partial sectional view taken along line 36B-36B of FIG.36A;

FIG. 36C is a detail exploded view of an adapter assembly cooperatingwith a tibial component according to additional features;

FIG. 36D is a partial sectional view taken along line 36D-36D of FIG.36C;

FIG. 37 is a sectional view of an exemplary adapter having a firstoffset;

FIG. 38 is a sectional view of another exemplary adapter having a secondoffset;

FIG. 39A is an exploded view of a fastener member and insert of theadapter assembly;

FIG. 39B is a partial exploded view of an adapter assembly;

FIG. 40A is an assembled view of a tibial component, adapter assemblyand stem according to one example of the present teachings;

FIG. 40B is a sectional view taken along line 40B-40B of FIG. 40A;

FIG. 41A is an assembled view of an exemplary femoral component, adapterassembly and stem according to one example of the present teachings;

FIG. 41B is an assembled posterior perspective view of a pair ofinterlocking augments, adapter assembly and femoral component accordingto one example of the present teachings;

FIGS. 42-45 are perspective views of various tibial components andbearings used in cooperation with a bone conserving hinged knee;

FIG. 46 is a superior view of an assembled hinged knee;

FIG. 47 is a sectional view taken along line 47-47 of FIG. 46;

FIGS. 48A and 48B are exploded perspective views of a hinged kneeprosthesis according to one example of the present teachings;

FIG. 49 is a sectional view of the hinged knee prosthesis of FIGS. 48Aand 48B shown assembled;

FIGS. 50-54 are perspective views of various augments according to thepresent teachings;

FIGS. 55A and 55B illustrates a kit of implants according to the presentteachings;

FIGS. 56-60 illustrate various augments shown during stages of assembly;

FIGS. 61-80B illustrate various instruments used for preparing a femurand tibia for receipt of the implants disclosed herein;

FIG. 81-104 illustrate exemplary sequences of using the instruments ofFIGS. 61-80B;

FIGS. 105-107 illustrate various apparatus for aligning an offsetadapter at a desired orientation prior to joining with a desired femoralor tibial component;

FIGS. 108-120 illustrate various instruments and a related sequence forpreparing a tibia for receipt of a tibial prosthesis;

FIGS. 121-140 illustrate various instruments and a related sequence forpreparing a femur for receipt of a femoral prosthesis; and

FIGS. 141 and 142 illustrate various instruments and a related sequencefor preparing a femur during a primary knee procedure.

DETAILED DESCRIPTION

At the outset, the instant disclosure provides a knee joint prosthesissystem having various knee joint prostheses that may be adapted for usein a revision knee procedure. Various tibial and femoral components aredescribed that may be used alone or as part of a cruciate retaining (CR)knee revision, posterior stabilized (PS) knee revision, fullyconstrained knee revision and hinged knee revision. As will bedescribed, the instant disclosure further provides various modularadapters, stems and augments that may be used in any combination withany of the tibial and femoral components disclosed herein. In otherwords, all of the components disclosed that are above and below thejoint line, such as the stems, adapters, augments, etc., can beinter-changeably used with any of the knee prostheses disclosed hereinand on the tibial or femoral side. Moreover, selection of any of theknee prostheses and related components from the knee joint prosthesissystem may be selected intra-operatively by the surgeon performing theprocedure.

With initial reference to FIG. 1, a knee joint prosthesis constructed inaccordance with the present teachings is illustrated and generallyidentified at reference number 10. The knee joint prosthesis 10 isgenerally shown to include a tibial component 12 that supports a bearing14 which engages an articulation surface of a femoral component (notshown). Insofar as the present teachings are concerned, it will beunderstood that the tibial tray 12 and bearing 14 can be adapted for usewith any suitable femoral component. For example, a first cruciateretaining (CR) bearing 14 is illustrated that is designed to articulatewith a CR femoral component. However, a fixed PS bearing may be employedthat is designed to articulate with a PS femoral component.

The tibial component 12 illustrated in FIG. 1 will be understood to bemodular in construction and generally include a stem 20, a tray 22, anda first adapter assembly 24. In a manner which will be discussed morefully below, the adapter assembly 24 can connect the tray 22 and thestem 20 so as to provide an offset to the stem 20 in the transverse orcoronal plane or in any other plane. Explaining further, when the stem20 is attached to the tray 22 through the first adapter assembly 24, acentral axis 25 of the stem 20 can be offset from a central axis 27 ofan inferiorly extending portion 28 of the tray 22. In the embodimentillustrated, the first adapter assembly 24 can provide a first offset ofapproximately 5 mm. It is appreciated that the offset can range from 0mm to approximately 5 mm or more and can be in any rotational directionrelative to the central axis 27. Alternatively, a stem 20 can beattached directly to the tray 22 (FIG. 29). In other words, the offsetaxis 25 can be rotated 360 degrees relative to the central axis 27 toprovide the surgeon with various intra-operative options to selectdepending on the patient's needs. Alternatively, the adapter assembly 24or stem 20 can be rotational keyed to provide only a limited range ofadjustment, such as providing only a single offset or two offsetpositions.

With reference to FIGS. 2 and 3A, the inferiorly extending portion 28 ofthe tibial tray 22 can define a female tapered receiving portion 30. Thefemale tapered receiving portion 30 can taper slightly as it extendsinto the inferiorly extending portion 28. A central aperture 32 can beformed through the tray 22 and the inferiorly extending portion 28 intothe female tapered receiving portion 30. The inferiorly extendingportion 28 may also define an exterior tapered augment receiving surface34. A retaining rail 36 (FIG. 2) can extend superiorly from a posterioredge of the tray 22. The tibial tray 22 can further include a pair ofposts 38 integrally formed on a superior surface at an anterior edgethereof. The posts 38 and rail 36 can cooperate to retain the modularbearing 14 in a fixed position on the tray 22. An alternate tibial tray22′ is shown in FIG. 3B.

The modular bearing 14 can be formed of ultra-high molecular weightpolyethylene (UHMWPE) with anterior and posterior recesses (notspecifically shown) to receive the posts 38 and rail 36, respectively,and with a uniformly flat inferior surface on its intercondylar andmedial/lateral portions for direct contact with the superior surface ofthe tray 22. The modular bearing 14 can be designed to be locked inposition with a transverse slide-in locking bar or clip 40 wedgedbetween the posts 38 and the bearing 14 in opposed grooves providedtherein for that purpose. A more detailed discussion of how the lockingbar cooperates with the posts and bearing may be found in commonly ownedU.S. Pat. No. 5,330,534 entitled “Knee Joint Prosthesis WithInterchangeable Components”, which is hereby incorporated by reference.Modular tibial trays and bearings as generally described above arecommercially available from Biomet Inc., the assignee of the presentdisclosure, as components of the Vanguard® Complete Knee System, whichincludes various sizes and configurations of trays, bearings and otherknee components for different patient requirements. The articulatingsurfaces of the modular bearing 14 can be substantially the same asprovided by the Vanguard® Complete Knee System.

Turning now to FIGS. 2, 4 and 5, the adapter assembly 24 can generallyinclude an adapter body 44 and a locking member or element 46 (FIG. 2).The adapter body 44 of the adapter assembly 24 can define a male taperedinsertion portion 48 having a passage 50 formed therethrough. A femaletapered receiving portion 52 can be formed in an offset body portion 53of the adapter body 44 for receiving a male tapered insertion portion 58of the stem 20. In one example, the female tapered receiving portion 52can be generally cylindrical. A skirt 54 can be defined at a transitionbetween the male tapered insertion portion 48 and the offset bodyportion 53.

With reference to FIG. 4, the male tapered insertion portion 48 of theadapter body 44 defines a first axis A₁ and the female tapered receivingportion 52 defines a second axis A₂. Further, in the embodimentillustrated, the first axis A₁ and the second axis A₂ are parallel toone another and spaced apart to provide the desired offset. In thisregard, multiple adaptors each having a different offset can be providedto provide the surgeon with intra-operative selection depending on thepatient's needs. Insofar as the adapter body 44 provides a 5 mm offset,the first and second central axes A₁ and A₂ are spaced apart 5 mm. Theadapter body 44′ can define a skirt 54′ having an alternateconfiguration. Other geometries are contemplated for the skirt 54, 54′.

The male tapered insertion portion 48 can taper slightly as it extendsaway from the adapter body 44. The female tapered receiving portion 52similarly tapers slightly as it extends into the adapter body 44 from anend of the adapter body 44. As will become appreciated from thefollowing discussion, various male tapered insertion portions (such asportion 48) can be inserted in various female tapered receiving portions(such as portion 52) to form a locking taper or Morse taper. The adapterbody 44 is illustrated to further define a laterally extending channel60 which intersects both the aperture 50 and the female taperedreceiving portion 52. In a manner to be described further below, thelocking element 46 can extend into the laterally extending channel 60where it ultimately couples the tray 22 to the stem 20.

As shown in FIGS. 2 and 6, the stem 20 can include an upper portion 64that cooperatively engages with the locking element 46. In theembodiment illustrated, the upper portion 64 of the stem 20 can includea fastener insert 66. Alternatively, the fastener insert 66 of the stem20 may be integrally formed to cooperate with the locking element 46.

The fastener insert 66 can include a distal portion 70 which can beexternally threaded for engaging an internally threaded aperture 72 ofthe male tapered insertion portion 58 of the stem 20. The fastenerinsert 66 can further include a central portion 74 having a hexagonal orother suitable cross-section which can be engaged by a tool (not shown)for rotating the fastener insert 66 into the stem 20. Further, thefastener insert 66 can include a proximal end 78 including an enlargeddiameter head 80.

The locking element 46 can be sized and configured to be insertedthrough an opening 81 in the sidewall of the adapter body 44 and intothe channel 60 for coupling of the stem 20 and the tray 22. The lockingelement 46 can include an upper surface 84 (see FIG. 2) having aninternally threaded aperture 86. The internally threaded aperture 86 canthreadably receive a fastener 90 which can extend through the centralaperture 32 provided in the tray 22. The fastener 90 can align with thecentral longitudinal axis 27 of the inferior portion 28 of the tray 22.

With additional reference to FIG. 7C, the locking element 46 canadditionally include an open end 94 and a bottom surface having a slot96. The slot 96 can intersect the open end 94. The open end 94 canreceive the head 80 of the stem insert 66 as the locking element 46 isinserted through the opening 60. The slot 96 can accommodate a reduceddiameter, central portion 100 of the fastener insert 66. The head 80 ofthe fastener insert 66 can have a diameter greater than a width of theslot 94 for coupling of the fastener insert 66 with the locking element46.

The locking element 46 can further include a closed end 104. The closedend 104 can be convexly curved. When the locking element 46 iscompletely inserted into the channel 60, the closed end 104 can be flushwith the sidewall of the adapter body 44.

In use, the fastener insert 66 can be screwed into the stem 20. Next,the adapter body 44 can be placed over the male insertion portion 64 ofthe stem 20 such that the male insertion portion 64 is received in apress fit within the female tapered receiving portion 52 of the adapterbody 44 and the upper end 78 of the fastener insert 66 extends into thelaterally extending channel 60.

The male taper extension 48 of the adapter 44 can now be press fit ontothe female tapered receiving portion 30 of the tray 12 with the adapterbody 44 oriented to provide the offset in the desired direction. Asviewed in FIG. 7B, the adapter body 44 may be rotated about the axis A₁prior to fastening to orient the stem 20 at the desired offset for aparticular patient. As a result, the stem 20 may extend at a pluralityof positions around a radius defined by the axes A₁ and A₂.Alternatively, the stem 20 may be keyed with the adapted body thus,precluding rotation. In addition, a set of stems may be provided havingvarious lengths suitable for a range of patients. Likewise, a set ofadapter bodies may be provided for providing various offsets.

At this point, the locking element 46 can be inserted into the laterallyextending channel 60 through the opening 81. Upon complete insertion,the locking element 46 can engage the fastener insert 66. The tray 22can be secured to the adapter body 44 by the threaded fastener 90 whichextends through the central aperture 32 of the tray 22 and threadablyengages the internally threaded aperture 86 of the locking element 46. Afurther discussion of offset stems and their application with respect tovarious tibial and femoral components may be found in commonly ownedU.S. patent application Ser. No. 10/934,282 filed Sep. 3, 2004 andentitled “Knee Joint Prosthesis”, which is hereby incorporated byreference. In this commonly owned Application, the tibial tray definesan inferiorly extending male portion whereas in the instant application,the tibial tray 22 defines the inferiorly extending the female receivingportion 30. In addition, while not specifically shown, the adapter body44 may alternatively define an axis A₂ that defines an angle withrespect to the axis A₁.

In another example, the male insertion portion 58 may be inserteddirectly into the female receiving portion 30 of the tray 22. In thisexample, another threaded fastener 90′ may be used that has a shortershaft for spanning an appropriate distance to mate directly with thethreaded aperture 72 of the stem 20. As shown in FIGS. 3A-3D, othertibial trays 22A, 22B, 22C and 22D, are shown for accommodating variouscombinations of fasteners 90, 90′, adapters 44, 44′ and stems 20.

Turning now to FIG. 8, a knee joint prosthesis according to anotherexample is shown and generally identified at reference number 110. Theknee joint prosthesis 110 includes a femoral component 112. The femoralcomponent 112 may be used as part of a posterior stabilized (PS) kneejoint prosthesis. A PS knee joint prosthesis can provide adequatestability in case of moderate deterioration or instability of a knee.This most typically occurs when the anterior and posterior cruciateligaments are sacrificed or dysfunctional and the medial and lateralcollateral ligaments remain functionally intact. The femoral component112 can include a first condylar portion 114 and a second condylarportion 116 that provide a first femoral bearing surface 118 and asecond femoral bearing surface 120, respectively. The first and secondcondylar portions 114 and 116 of the femoral component 112 can beinterconnected by an inner condylar portion 122 that defines anintercondylar recess 124. A superiorly extending portion 130 may beformed on the femoral component 112. The superiorly extending portion130 can include a generally tapered outer body to receive the augmentsdescribed herein and define a female tapered receiving portion 132.

According to the present teachings, the female tapered receiving portion132 of the femoral component 112 may be configured to accept one of theadapter bodies 44, 44′ described above. In this way, the male taperedinsertion portion 48 of the adapter body 44 can be adapted to beinserted and press-fit into the female tapered receiving portion 132 ofthe femoral component 112. As can be appreciated, the first axis A₁ andthe second axis A₂ are parallel to one another and spaced apart. Again,the exemplary adapter assembly 24 has been described as having a 5 mmoffset however, other adapter bodies may be provided having variousoffsets. A locking element 46 and stem 20 may be used according to thedescription above.

Turning now to FIGS. 9-14, a knee joint prosthesis according to anotherexample is shown and generally identified at reference number 210. Theknee joint prosthesis 210 is generally shown to include a tibialcomponent 212 that supports a rotating constrained bearing 214. Thetibial component 212 can generally include a substantially planarplatform-like tibial tray 216 (FIG. 10) and an inferiorly extendingportion 218. The inferiorly extending portion 218 can define a taperedfemale receiving portion 220 and an outer tapered body for receivingaugments disclosed herein.

The tibial tray 216 can further include a superiorly extending post 224.A transition between the tibial tray 216 and the superiorly extendingpost 224 can be defined by a varying radius R, or more specificallytransition between a radius R₁ having a radius of approximately 0.50inches, and a radius R₃ having a radius of approximately 1.50 inches. Anintermediate radius R₂ can have a radius of approximately 0.38 inches.It is appreciated that the radius R may define other dimensions. Thetransition of the varying radius R can minimize stresses experienced onthe superiorly extending post 224. An axis A₃ (FIG. 14) defined throughthe post 224 can be laterally offset in the posterior direction relativeto an axis A₄ defined through the inferiorly extending portion 218. Athreaded aperture 228 can be formed through the anterior portion of thetibial tray 216. The threaded aperture 228 can extend generallyperpendicular to the axis A₄.

The inferiorly extending portion 218 can define a tapered augmentreceiving surface 230. The tibial tray 216 can be formed fromcobalt-chromium-molybdenum or any other suitable biocompatible material.A top 232 (FIG. 10) of the tibial tray 216 can be highly polished toprovide a substantially smooth tibial bearing surface 234.

The rotating bearing 214 can have a substantially planar inferiorbearing surface 238 (FIG. 11) which can rotatably move relative to thehighly polished tibial bearing surface 234. The rotating bearing 212 canfurther include a first superior articulating or bearing surface 240 anda second superior articulating or bearing surface 242. The bearingsurfaces 240 and 242 can be formed anteriorly and laterally from acentral superiorly extending portion 244. The first bearing surface 240and the second bearing surface 242 can articulate with respectivebearing surfaces of a first and second condyle of a constrained femoralcomponent (not shown). The rotating bearing 212 can be formed from asurgical grade, low friction, and low wearing plastic, such as UHMWPE orother suitable material. As shown in FIG. 13, a posterior edge 246 ofthe tibial tray 216 can define a surface that defines an angle 247relative to a posterior edge 250 of the bearing 214. The angle 247 canbe approximately 8 degrees. Other angles are contemplated.

Turning now to FIG. 14, a stem 20 is shown received directly into thefemale tapered receiving portion 220 of the tray 216. Again, instead ofinserting a stem 20 directly into the female tapered receiving portion220 of the tray 216, an adapter body 44 or 44′ may be used. The stem 20can include a fastener insert 66′. The fastener insert 66′ can include adistal portion 70′ which is externally threaded for engaging aninternally threaded aperture 72 of the male tapered insertion portion 64of the stem 20. The fastener insert 66′ can further include a centralportion 74′ having a hexagonal or other suitable cross-section which canbe engaged by a tool (not shown) for rotating the fastener insert 66′into the stem 20. Further, the fastener insert 66′ can include an upperend 78′ including a conical engaging head 80′. A set screw 252 can beadvanced through the threaded aperture 228 of the tibial tray 216 toengage the conical engaging head 80′. In this way, advancement of theset screw 252 can secure the fastener insert 66′, and therefore, thestem 20 in a secure position. It is appreciated that when utilizing theadapter body 44, a fastener such as fastener insert 66′ but having alonger shank, may alternately be used for threadably securing to thelocking element 46.

Turning now to FIGS. 15-20, a hinged knee joint prosthesis constructedin accordance with the present teachings is illustrated and generallyidentified at reference number 310. The knee joint prosthesis 310 isgenerally shown to include a tibial component 312 that supports abearing 314 which engages an articulation surface of a femoral component316. The tibial component 312 can generally include a substantiallyplanar platform-like tibial tray 318 and an inferiorly extending portion320. The inferiorly extending portion 320 can define a tapered femalereceiving portion 322.

With additional reference to FIG. 16A, the tibial tray 318 can furtherinclude a superiorly extending post 324. As will be described, a cap 326can be securably inserted into an elongate bore 328 defined at aterminal opening of the superiorly extending post 324. A threadedaperture 330 can be formed through the tibial tray 318. The threadedaperture 330 can extend generally perpendicular to an axis defined bythe superiorly extending post 324. The tibial tray 318 can be formedfrom cobalt-chromium-molybdenum or any other suitable biocompatiblematerial. A set screw (not shown) can be advanced through the threadedaperture 330 of the tibial tray 318 to engage a conical engaging head ofa fastener insert (as described in detail above regarding FIG. 14). Inthis way, advancement of the set screw can secure the fastener insert,and therefore the adapter body 44 or the stem 20 in a secure position.The top of the tibial tray 318 can be highly polished to provide asubstantially smooth tibial bearing surface 331.

The rotating bearing 314 can have a substantially planar inferiorbearing surface 332 which can rotatably move relative to the highlypolished tibial bearing surface 331. The rotating bearing 314 canfurther include a first superior articulating or bearing surface 336 anda second superior articulating or bearing surface 338. The first bearingsurface 336 and the second bearing surface 338 can articulate withrespective bearing surfaces of a first and second condyle 340 and 342,respectively of the femoral component 316. Again, as described above,the bearing surfaces may be similar to those provided in the Vanguard®Complete Knee System. To accommodate guiding movement of the femoralcomponent 316, the bearing 314 can include a stabilizing post 350 whichcan project superiorly from the bearing surface. The stabilizing post350 can include a fin-like body 352 having a raised posterior portion354 and a lower anterior portion 356. The body 350 can define a firstand second laterally spaced-apart sides 360 and 362 (FIG. 17). The firstand second sides 360 and 362 of the stabilizing post 350 can bepositioned so as to extend into an intercondylar recess 366 (FIG. 15) ofthe femoral component 316. A stabilizing post aperture 370 can be formedin a superior/inferior direction through the body 350.

A passage 372 can be formed through the raised posterior portion 354 ofthe body 350. The passage 372 can extend generally through the first andsecond sides 360 and 362 of the stabilizing post 350 in a directiongenerally perpendicular to the stabilizing post aperture 370. Therotating bearing 314 can be formed from a surgical grade, low friction,and low wearing plastic, such as UHMWPE or other suitable material.

An alternate stabilizing post 350′ is shown in FIG. 16B that accepts acap or fastener 326′.

The first and second condylar portions 340 and 342 of the femoralcomponent 316 can be interconnected by an inner condylar portion 380that defines the intercondylar recess 366. The intercondylar portion 380can include a first lateral sidewall 382 and a second lateral sidewall384 (FIG. 17) which can be planar and substantially parallel to eachother. The first and second lateral sidewalls 382 and 384 can furtherdefine hinge passages 388 formed respectively therethrough.

Anterior portions of the first and second lateral sidewalls 382 and 384can be connected by an anterior surface 390 (FIG. 15) of theintercondylar portion 380. In one example, the anterior surface 390 ofthe intercondylar portion 380 can angle anteriorly in an inferiordirection at approximately 60 degrees with respect to a superior surfaceof the intercondylar portion 380. A superiorly extending portion 392 maybe formed on the femoral component 316 and generally extend from asuperior surface 394 (FIG. 16A). The superiorly extending portion 392can include a generally cylindrical body and define a female taperedreceiving portion 394.

A hinge post 396 can securably extend through the respective hingepassages 388 of the first and second lateral sidewalls 382 and 384 ofthe femoral component 316 and through the passage 372 in the bearing314. Of note, the lateral sidewalls 382 and 384 of the femoral component316 can be positioned proximate an inboard portion of the respectivefirst and second condyles 340 and 342. In this way, host bone need notbe sacrificed in areas outboard to the lateral sidewalls 382 and 384. Ascan be appreciated, during use, the femoral component 316 can rotateabout the hinge pin 396.

With reference to FIGS. 17-20, an exemplary sequence of assembling thefemoral component and bearing is shown. FIG. 17 illustrates an explodedview of the respective femoral component 310, hinge pin 396 and bearing314. As viewed in FIG. 18, the femoral component 310 is placed onto thebearing 314 such that the respective passages 372 and 388 are aligned.FIGS. 19-20 show the hinge pin 296 inserted into the passages 372 and388.

With reference now to FIGS. 21-25 a plurality of exemplary augments foruse with any of the knee joint prostheses described above will beexplained in detail. FIGS. 21-23B illustrate a first pair of augments400 and 402. The first augment 400 can generally define a body 404having first end 406 and a second end 408. The body 404 can furtherdefine a consistent radius portion 410 at the second end and 408 anoutwardly tapered radially extending portion 412 near the first end 406.The consistent radius portion 410 can define a tapered receiving bore416 formed therethrough. The receiving bore 416 can taper from the firstend 406 to the second end 408. A first step 420 may be formed in thebody 404 between the consistent radius and the radially extendingportions 410 and 412, respectively. As can be appreciated, a collectionof first augments may be provided having various dimensions andconfigurations suitable for a particular patient.

The second augment 402 can generally define a body 424 having first end426 and a second end 428. The body 424 can further define a consistentradius portion 430 at the first end 426 and an outwardly taperedradially extending portion 432 near the second end 428. The consistentradius portion 430 can define a tapered receiving bore 436 formedtherethrough. The receiving bore 436 can taper from the first end 426 tothe second end 428. A second step 440 may be formed at the second end428 between the consistent radius and the radially extending portions430 and 432, respectively. As can be appreciated, a collection of firstaugments may be provided having various dimensions and configurationssuitable for a particular patient.

As will be described in detail later, the first and second augments 400and 402 may be used singly or as a combination. As shown in FIG. 23B,the first and second augments 400 and 402 can interlock or mate at thefirst and second steps 420 and 440 when used concurrently with any ofthe tibial and femoral components described above.

With reference now to FIGS. 24 and 25, a third augment 450 is shown. Thethird augment 450 can generally define a body 452 having a first end 454and a second end 456. The body 452 can further define a pair of wingportions 460 extending radially therefrom to provide rotationalstability to either the femoral component or the tibial component. Inone example, the wing portions 460 may be offset toward the first end454. The body 452 can define a tapered receiving bore 464 formedtherethrough. The receiving bore 464 can taper from the second end 456to the first end 454.

According to the teachings of the present disclosure, the receivingbores 416, 436 and 464 of each of the augments 400, 402 and 450 can beslidably press-fit onto any of the inferior extensions of the tibialtrays described above. More specifically, the receiving bores can definea tapered interlock with the tapered augment receiving surfaces of theinferior extensions of the tibial trays. Likewise, any of the sameaugments can also be slidably press-fit onto any of the superiorextensions of the femoral components described above. More specifically,the receiving bores can define a tapered interlock with the taperedaugment receiving surfaces of the superior extensions of the femoralcomponents. As such, the respective tapered surfaces can cooperate toform a Morse taper.

To illustrate this compatibility, a second augment 402 is shown securedto the superior extension 130 of the femoral component 112 (FIG. 26). Ifa surgeon desires to account for additional bone loss, the first augment400 may also be advanced onto the superior extension 130 of the femoralcomponent 112 (FIGS. 27 and 29). As shown, the respective first andsecond steps 420 and 440 cooperate to mate or form an interlock.

With reference to FIG. 29, a first and second augment 400 and 402 areshown secured to the inferior extension 28 of the tibial tray 22.Notably, the first and second augments 400 and 402 may be used with orwithout the adapter. It is appreciated, that any of the augments may beused with or without the adapter assemblies described above. FIG. 30illustrates the third augment 450 secured to the inferior extension 28of the tibial tray 22.

Turning now to FIGS. 31 and 32, another tibial component 522 is shown.The tibial component 522 can define one or more (such as a pair) ofblind bores 524 and at least one opening 526 formed on an inferiorsurface. A recessed portion such as pocket 530 may also be optionallyformed on an inferior surface of the tibial component 522. An augment540 can define one or more (such as a pair) of complementary locatingpegs 542 and at least one complementary opening 544. The augment 540 canbe adapted to secure onto the inferior surface of the tibial component522 to compensate for bone loss. As can be appreciated, an augment maybe provided on one of a lateral or medial portion, or both, of thetibial component 522. During assembly, the locating peg 542 may nestwithin a blind bore 524. A fastener (not shown) may be inserted throughthe respective openings 526 and 544. Another augment 540′ having atleast one peg 542′ can be provided for the opposite of the medial andlateral sides of the inferior surface of the tibial component 522. Inanother example (FIG. 32), an augment 540″ suitable for connecting toeither of the medial and lateral sides is provided. In such an example,pegs (such as pegs 542, FIG. 31) need not be provided. As can beappreciated, a plurality of augments 540 can be provided having variousthicknesses such that a surgeon can assemble a particular augmentsuitable for a given patient. A stem 20 can be fixedly accepted into afemale tapered extending portion 560 of the tray.

FIG. 33 illustrates another augment 590 that defines a tapered receivingbore 592 formed therethrough. The tapered receiving bore 592 can beslidably press-fit onto any of the inferior extensions of the tibialtrays and/or the superior extensions of the femoral components describedabove. A portion of the augment 590 can optionally be formed of porousmetal 594. The porous metal 594 can comprise porous titanium alloy forexample. The augment 590 can define an inner solid metal sleeve portionand an outer porous metal sleeve portion 594. Again, according to thepresent teachings, the respective femoral components, tibial components,bearings and/or augments may be part of a kit wherein a surgeon mayintra-operatively select a desired component or components needed for aparticular patient.

Turning now to FIGS. 34-36B, the modular tibial component 22 (asdescribed above with respect to FIGS. 1-3A) is shown cooperating with anadapter assembly 600 according to additional features. The adapterassembly 600 can cooperate with the stem 20. In a manner which will bediscussed more fully below, the adapter assembly 600 can connect thetray 22 and the stem 20 so as to provide an offset to the stem 20 in thetransverse or coronal plane or in any other plane. Explaining further,when the stem 20 is attached to the tray 22 through the first adapterassembly 600, the central axis 25 of the stem 20 can be offset from thecentral axis 27 of the inferiorly extending portion 28 of the tray 22.In the embodiment illustrated, the adapter assembly 600 can provide afirst offset of approximately 5 mm. It is appreciated that the offsetcan range from 0 mm to approximately 5 mm or more and can be in anyrotational direction relative to the central axis 27. In other words,the offset axis 25 can be rotated 360 degrees relative to the centralaxis 27 to provide the surgeon with various intra-operative options toselect depending on the patient's needs. Alternatively, the adapterassembly 600 or stem 20 can be rotational keyed to provide only alimited range of adjustment, such as providing only a single offset ortwo offset positions.

With continued reference to FIGS. 34-36D and additional reference toFIGS. 37-39B, the adapter assembly 600 can generally include an adapterbody 604 and a locking member or element 606. The adapter body 604 ofthe adapter assembly 600 can define a male tapered insertion portion 608and a female tapered receiving portion 610. The male tapered insertionportion 608 can define a threaded bore 611. The female tapered receivingportion 610 can be formed in an offset body portion 612 of the adapterbody 604 for receiving a male tapered insertion portion 58 of the stem20. The adapter body 604 can define flats 614 on an outer surface forgripping and facilitating alignment as will be described. A skirt (notshown), similar to the skirt 54 formed on the adapter body 44illustrated in FIG. 2, can be defined at a transition between the maletapered insertion portion 608 and the offset body portion 612. Anon-skirted transition can alternatively be formed as shown herein. Abore 614 can be defined from an outer surface of the adapter body 604 tothe female tapered receiving portion 610. The bore 614 can definethreads 616 that threadably receive the locking member 606.

With reference to FIG. 37, the male tapered insertion portion 608 of theadapter body 604 defines a first axis A₅ and the female taperedreceiving portion 610 defines a second axis A₆. Further, in theembodiment illustrated, the first axis A₅ and the second axis A₆ areparallel to one another and spaced apart to provide the desired offset.In this regard, multiple adaptors each having a different offset can beprovided to provide the surgeon with intra-operative selection dependingon the patient's needs. Insofar as the adapter body 604 provides a 5 mmoffset, the first and second central axes A₅ and A₆ are spaced apart 5mm. Again, the adapter body 604 can define axes having an alternateoffset. In one such alternate configuration, an adapter body 604′ (FIG.38) includes a male tapered insertion portion 608′ that defines a firstaxis A₇ and the female tapered receiving portion 610′ that defines asecond axis A₈. The adapter body 604′ can define an offset of 2.5 mm.

The male tapered insertion portion 608 can taper slightly as it extendsaway from the adapter body 604. The female tapered receiving portion 610similarly tapers slightly as it extends into the adapter body 604 froman end of the adapter body 604. As will become appreciated from thefollowing discussion, various male tapered insertion portions (such asportion 608) can be inserted in various female tapered receivingportions (such as portion 610) to form a locking taper or Morse taper.In a manner to be described further below, the locking member 606 canextend into the bore 614 where it ultimately engages a fastener insert620.

The fastener insert 620 can include a distal portion 622 which can beexternally threaded for engaging the internally threaded aperture 72 ofthe male tapered insertion portion 58 of the stem 20. The fastenerinsert 620 can further include a central portion 624 and a proximalportion 626. The proximal portion 626 can define a conical engaging head630. A gripping detail 632 (such as, but not limited to, a hex-bore forreceiving an Allen wrench), can be formed in an upper surface of theproximal portion 626. As will be described in more detail, the fastenerinsert 620, or more specifically the conical engaging head 630 can beformed of a first biocompatible material while the locking member 606can be formed of a second biocompatible material. The secondbiocompatible material can be a higher durometer (harder) material thanthe first biocompatible material.

Turning now to FIGS. 36C and 36D, a tibial tray 636 according toadditional features is shown. As will be described more fully herein,the tibial tray 636 can be part of a bone-conserving hinge kneeprosthesis (FIG. 48A). The tibial tray 636 can define a superiorlyextending stub 637 and an inferiorly extending portion 638 that definesa female tapered receiving portion 640. The inferiorly extending portion638 can define an exterior tapered augment receiving surface 642. Thetibial tray 636 can define a threaded passage 646 formed through thetray portion of the tibial tray 636. The treaded passage 646 can beadapted to threadably accept the locking member 606. Unlike the cruciateretaining tibial tray 22 (FIG. 34) that provides the central aperture 32for receiving the fastener 90′ in the superior/inferior direction, thetibial tray 636 can provide the threaded passage 646 for receiving thelocking member 606 in the anterior/posterior direction.

With reference now to FIGS. 39A-40B, an exemplary sequence of assemblingthe tibial tray 636, the adapter body 604, and the stem 20 will bedescribed. At the outset, the fastener insert 620 can be threaded intothe threaded bore 611. In one example, the fastener insert 620 can bethreaded until the central portion 624 engages a terminal surface 650 ofthe male tapered insertion portion 608 of the adapter body 604. At thispoint, the stem 20 can be coupled to the adapter body or the adapterbody 604 can be coupled to the tibial tray 636. While the order can bereversed, the adapter body 604 can be coupled to the tibial tray 636, byinserting the male tapered insertion portion 608 of the adapter body 604into the female tapered receiving portion 640 of the tibial tray 636.The surgeon can then rotate the male tapered insertion portion 608within the female tapered receiving portion 640 to attain the desiredorientation. As will be described later, the instant disclosure providesvarious tools for verifying a correct orientation of the adapter body604 prior to securing the adapter body 604 in a fixed position relativeto the tibial tray 636. Once the desired orientation has been attained,the locking member 606 can be threaded from an unsecured position (FIG.36C) into engagement with the conical engaging head 630 to a securedposition (FIG. 36D).

As mentioned above, the locking member 606 can be formed of abiocompatible material that is harder than the fastener insert 620. As aresult, a distal end 654 of the locking member 606 can deform (e.g.create a depression at) an interface area of the conical engaging head630. The deformed area is identified at reference numeral 656 (FIGS. 39Aand 40B). By deforming an area 656 of the fastener insert 620, thelocking function of the locking member 606 can be improved by providinga greater resistance to separation. Explained further, the resultantdepression can inhibit sliding, rotation, or other relative movementbetween the locking member 606 and the fastener insert 620.

Next, the stem 20 can be coupled to the adapter body 604 by driving thelocking member 606 (i.e. another identical locking member 606) into thefastener insert 620 (i.e. another identical fastener insert 620).

According to another feature, the threads 616 defined by the bore 614can define a thread profile that is slightly different (i.e. pitch) thanthreads 662 defined by the locking member 606. Alternatively, one of thethreads 616 or 662 can be deformed initially. Such a relationship canallow the locking member 606 to be retained within the bore 614 uponinitial handling by a surgeon. In other words, the locking member 606can already by positioned within the bore such that the surgeon wouldnot need to locate the distal tip 654 of the locking member 606 into thebore 616 (i.e. mate two separate components). It is appreciated thatsuch thread configuration would not preclude rotation of the lockingmember 606 within the bore 616 during fastening.

Turning now to FIG. 41A, the adapter assembly 600 including the adapterbody 604 and the locking member 606 are shown assembled with a femoralcomponent 112′. The femoral component 112′ is substantially similar tothe femoral component 112 (FIG. 8), but can define a threaded bore 668formed in a femoral box 670. As can be appreciated, the threaded bore668 can provide a similar function to the threads 616 of the bore 614 ofthe adapter body 604. As a result, a locking member 606 can be driven toengage a conical engaging head 630 of fastener insert 620.

As shown in FIG. 41B, a skirt 54″ is shown on the adapter body 604. Theskirt 54″ generally defines a flared contour portion that can provide agenerally smooth geometrical transition onto the outwardly taperedradially extending portion 432 (see also FIG. 21) of the augment 402.The geometrical transition between the skirt 54″ and the augment 402 canreduce otherwise sharp transitions between implanted components toprovide a favorable nesting configuration with surrounding bone in animplanted position. Explained more specifically, the male taperedinsertion portion 608 of the adapter 604 can define an attachment axis671. The outwardly tapered radially extending portion 432 of the body424 can define a plane 673. The flared contour portion of the skirt 54″can taper generally along the plane 673 in an implanted position. Theskirt 54″ can therefore cooperate with the augment 402 to effectivelyfill bone voids.

As can now be appreciated, the instant disclosure provides a simplifiedset of interchangeable components wherein an adapter assembly 600 can beused on either side of the joint line (e.g. with a tibial component,such as described in relation to FIG. 35, and also a femoral component,such as described in relation to FIG. 41). Moreover, the locking member606 and fastener insert 620 combination can be used in several distinctareas as described above. Additionally, the augments such as disclosedin FIGS. 21-25 can be used in cooperation with either a superiorlyextending portion (such as portion 130, FIG. 8) of a femoral componentor an inferiorly extending portion (such as portion 638, FIG. 36C) of atibial component.

Turning now to FIGS. 42-49, additional components that may be used incooperation with the tibial tray 636 will be described in greaterdetail. As explained, the tibial tray 636 can be used as part of abone-conserving hinge knee prosthesis. The tibial tray 636 can cooperatewith a bearing 672. A keel 680 can define a first bore 682 for receivingthe superiorly extending stub 637, and a second bore 684 for receivingan axle 686. A pair of hubs 688 can engage opposite ends of the axle686. In one example, a biasing member 687 can bias against an outersurface on the keel 680 to bias the axle 686 outward.

The keel 680 can be intraoperatively coupled to the femoral component692 by depressing the axle 686 in a direction inwardly and locating thekeel 680 generally into the femoral box 696 of the femoral component 692until the axle 686 aligns with passages 695 and 697 formed in thefemoral box. The hubs 688 can nest in the passages 695 and 697 onopposite ends of the axle 686. The axle 686 can bias outwardlyencouraging the hubs 688 to seat into the passages 695 and 697. As canbe appreciated, during use, the hubs 688 can provide a rotationalsurface for supporting the axle 686. The hubs 688 can be formed of anysuitable bearing material such as PEEK, polyethylene, carbon reinforcedPEEK. A pin 700 can then be inserted into the keel 680 to inhibit inwardcompression of the axle 686.

A shoe 690 can be disposed intermediate of the keel 680 and a femoralcomponent 692. The femoral component 692 can define a threaded bore 694through the box 696. A superiorly extending portion 698 can receive amale tapered insertion portion 608 of the adapter body 604. The lockingmember 606 can be used as described above to engage a fastener insert620 (not specifically shown) extending proud from the male insertionportion 608. Alternatively, a fastener can extend superiorly though thefemoral component 692 to securably mate with the adapter body 604 (suchas shown in FIG. 8). A horseshoe clip 702 can securably nest in anannular pocket 704 defined on the stub 637.

With reference now to FIGS. 50-54, additional augments are shown. Anaugment 710 can define a substantially symmetric profile for securing toeither a medial or lateral inferior side of a tibial tray (i.e. such asa tibial tray 22D, FIG. 3D). Passages 712 can be formed through theaugment 710 for receiving a fastener (not shown) in an assembledposition. Augments 716 and 718 can define passages 720 and 722,respectively for receiving a superiorly extending portion 724 of afemoral component 730 (see FIG. 58). The augments 716 and 718 can definea profile unique for cooperating with a medial or lateral side of afemoral box 732. The augment 716 can be implanted to occupy an area ofbone loss on a medial side of the femoral component 730. The augment 718can be implanted to occupy an area of bone loss on a lateral side of thefemoral component. Augments 734 and 736 can define passages 738 and 740respectively (FIG. 59). The augments 734 and 736 can be usedindividually or in combination. The respective passages 720, 722, 738and 740 and the superiorly extending portion 724 of the femoralcomponent 730 can define conical engaging surfaces that are adapted toprovide a friction fit formed by a Morse-type taper. The augments 734and 736 can define a profile different than the augments 716 and 718.

Returning now to FIG. 53, another augment 744 is shown. The augment 744can define a passage 746. In one example, the augment 744 can besymmetric for coupling to either a medial or lateral surface of thefemoral component 730. Threaded blind bores 750 and 752 can be definedon the femoral component 730 for accepting a fastener (not shown) forsecuring an augment 744. Another augment 744′ can be provided (that canhave a mirror image profile relative to the augment 744) forcompatibility with only the medial (or lateral) side of the femoralcomponent.

With reference to FIGS. 54 and 57, a saddlebag augment 754 having acentral passage 756 is shown. The central passage 756 can receive thesuperiorly extending portion 724 of a femoral component 730. As with theother augments provided herein, the central passage 756 and thesuperiorly extending portion 724 can define conical engaging surfacesthat are adapted to provide a friction fit formed by a Morse-type taper.FIG. 60 illustrates a femoral component 730 having the winged augment450 (FIG. 24) secured to the superiorly extending portion 724.

Each of the augments disclosed herein can be formed of biocompatiblematerial such as solid metal, porous metal or a combination of solidmetal and porous metal. In one example, the solid metal or porous metalcan comprise stainless steel, titanium, titanium alloys, cobalt-chromiumalloys and other materials that are suited for use in a biocompatibleenvironment. As is generally known in the art, porous metal can providea suitable surface area for encouraging ingrowth of natural bone and/orsoft tissue. Various compositions and methods of making such porousmetal may be found in co-pending applications, U.S. Ser. Nos.11/111,123, filed Apr. 21, 2005; Ser. No. 11/294,692, filed Dec. 5,2005; Ser. No. 11/357,868, filed Feb. 17, 2006 each entitled “Method andApparatus for Use of Porous Implants”; U.S. Ser. No. 11/546,500, filedOct. 11, 2006, entitled “Method for Use of Porous Implants”; U.S. Ser.No. 11/709,549, filed Feb. 22, 2007, entitled “Porous Metal Cup withCobalt Bearing Surface; and U.S. Ser. No. 11/357,929, filed Feb. 17,2006, entitled “Method and Apparatus for Forming Porous Metal Implants”,all of which are also assigned to Biomet, Inc., of Warsaw Ind., whichare incorporated herein by reference.

FIG. 55A illustrates a kit of components 760. The kit of components canbe used interchangeably as discussed herein. The stems can definevarious lengths and diameters. The adapters can define various offsets.FIG. 55B illustrates such interchangeability. For instance, a surgeoncan intraoperatively select a desired femoral component A, a tibialcomponent B, a bearing C, and augment D and an offset adapter E. Whilenot shown, a suitable stem (such as stem 20) can also be coupled to theoffset adapter E as described herein.

As described herein, the tapered female receiving portions have beendescribed as receiving the tapered male insertion portions by way ofpress-fit. Explained further, the female receiving portions and maleinsertion portions all define conical engaging surfaces adapted toprovide a friction fit formed by a Morse-type taper.

With reference now to FIGS. 61-77, exemplary tools for implanting afemoral component and offset adapter according to the present teachingsare shown. A distal resection cutting guide 800 (FIG. 61) can include adistal resection block 802 and a removable bracket portion 804 having apair of dials 806, 808 for selecting a desired orientation (i.e. valgusangle etc.). The distal resection block 802 can define resection slotsof +0, +4, +8, and +12 mm, collectively referred to at reference 810 fordistal resection. In one example, the +0 slot can resect from the mostprominent condyle as a clean-up cut. Other configurations arecontemplated. If there is a defect, the +4, +8, or the +12 mm slot canbe used for later use with a respective 4, 8 or 12 mm distalaugmentation block.

A distal cutting block 812 (FIGS. 62A-62D) can define lateral anteriorand posterior slots 822 and 824 and anterior and posterior chamfer slots826 and 828. The distal cutting block 812 can be referred to herein as a“cutting” block. First and second partially overlapping bores 830 and832 can be defined through a central portion 834 of the distal cuttingblock 812. As will become appreciated, one of the bores 830 or 832 canbe aligned for use with a right femur while the other can be aligned foruse with a left femur. A mark 836, 837 can be defined adjacent to therespective bores 830, 832. A rotatable offset bushing 838 (FIG. 66) canbe selectively received within either of the overlapping bores 830 and832. The offset bushing 838 can define an offset passage 840 and indicia842. The offset passage 840 can be laterally offset relative to alongitudinal axis of the offset bushing 838. A plurality of offsetbushings (such as offset bushing 838′, FIG. 67) can be provided thatprovide various offsets suitable for a range of patient needs. In theexamples shown, the offset bushing 838 can provide a 5 mm offset and theoffset bushing 838′ can provide a 2.5 mm offset. A bushing 838″ (FIG.68) can have a zero offset. Augment trials 844 (FIG. 63A) can beselectively secured to an inboard face 868 (FIG. 62B) of the distalcutting block 812. The augment trials 844 can define a series of detents870 for selectively capturing around a fastener 872 (FIGS. 64A and 64B).The series of detents 870 can locate the augment trials 844 at a desiredlocation.

A femoral offset template 876 (FIGS. 70A and 70B) can define a pluralityof apertures 880 for locating the fastener 872 and augment trial 844 atvarious locations. In one example, an offset template can be unique to aleft femur (e.g. FIGS. 70A and 70B) or right femur (e.g. template 876′,FIG. 71). A universal revision alignment member 882 (FIG. 69) can definea pocket 884 for receiving the bushing 838 (or 838′). A mark 886 can bedefined on the pocket 884 for aligning with the indicia 842. A tibialtemplate 890 (FIG. 78) can be provided for use during tibialpreparation. Additional description of the tibial template 890 may befound in commonly owned patent application Ser. No. 10/702,335, entitled“Tibial Preparation Apparatus and Method”, filed Nov. 6, 2003, thedisclosure of which is incorporated herein by reference. The tibialtemplate 890 can cooperate with an augment cut block 892. An implantboss reamer bushing 896 (FIG. 76) can be provided for receipt into thepocket 884 of the alignment member 882. Of note, the universal revisionalignment member 882, offset bushing 838, and reamer bushing 896 can allbe used with either the femoral offset template 876 or the tibialtemplate 890.

A tibial bushing stop 900 (FIG. 77) can be provided for locating betweenthe reamer bushing 896 and a collar 902 of a reamer bit 904 (FIG. 65).The tibial bushing stop 900 can be used to limit a reaming depth in thetibial canal when reaming a tibial bore. As can be appreciated, thedepth of a reamed tibial canal can be shallower than a depth of a reamedfemoral canal. An offset adapter rasp bushing 910 (FIG. 74) can define ahalf-moon shaped passage 912. The half-moon shaped passage 912 candefine a flat 914. The offset adapter rasp bushing 910 can cooperatewith the pocket 884 of the universal revision alignment member 882(during either femoral or tibial offset bore preparation). The offsetadapter rasp bushing 910 can define indicia 918 for aligning with themark 886 on the pocket 884. As will be described, the offset adapterrasp bushing 910 can be rotated to dial in a desired orientation thatcorresponds to the desired offset orientation of the adapter body 604(FIG. 34). Another offset adapter rasp bushing 710′ (FIG. 75) can defineanother offset.

A rasp 922 (FIGS. 72A and 72B) can define an impacting portion 924 on adistal end 926, and a handle 930 on a proximal end 932. A planar surface934 can be defined along the impacting portion 924. The planar surface934 can cooperate with the flat 914 of the offset adapter rasp bushing910 to locate the rasp 922 in a desired orientation.

A posterior stabilized box guide 940 or 942 (FIGS. 80A and 80B) or canbe provided for preparation of a posterior stabilized femur. Slots 944,946 can be defined through the posterior stabilized box guide 940 and942, respectively for guiding a cutting member at a given location. Theposterior stabilized box guide 940 can define passages 950 for acceptingthe augment trials 844 in a similar manner described above.

An exemplary sequence of preparing a femur F for accepting a femoralcomponent having an offset adapter will now be described. At the outset,the distal femur F can be exposed and a femoral (intramedullary) canal954 can be reamed until cortical contact is achieved using a reamer 956(FIG. 81). Next, the distal cutting guide 810 can be secured to thedistal femur F and aligned to a desired orientation using the dials 806,808. The bracket portion 804 can then be removed from the block 802,leaving the distal resection block 802 on the anterior bone. The reamer956 may be left in the bone F. While avoiding the reamer 956, distalresection through the selected slots 810 can be performed using asawblade 960. The distal cutting guide 810 can be removed while leavingin the reamer 956 (FIG. 83B).

If a distal augment cut is required, an augment trial 844 (or trials)can then be snapped onto the back side of the cutting block 812 (FIG.83C). Next, the offset bushing 838 can be inserted into the appropriateoverlapping bore 830 of the cutting block 812. The cutting block 812 isthen inserted over the reamer shaft 956 such that the reamer shaft 956locates through the offset bore 840 of the offset bushing 838 (FIG. 84).The offset bushing 838 is then rotated (thereby translating the cuttingblock 812 around the distal femur F) until the desired position of thecutting block 812 is attained. A bolt (not shown) extending through ananterior passage 960 in the cutting block 812 can then be tightened topreclude further movement of the offset bushing 838. The cutting block812 can then be secured to the distal femur F such as by driving nails962 through holes 964 provided on the cutting block 812. The alignmentnumber (i.e. the indicia 842 corresponding to the mark 836) is noted.The offset bushing 838 can then be removed. The anterior and posteriorbone can be resected followed by the anterior and posterior chamfer cutsusing a sawblade 966 (FIG. 85).

The cutting block 812 can then be removed from the distal femur F whileleaving the reamer 956 in place (FIG. 86). Augment trials 844 can thenbe coupled to the back side of the femoral offset template 876 using adesired hole 880. Next, the universal revision alignment member 882 canbe coupled to top side of the femoral template 876 (FIG. 88). The offsetbushing 838 can be inserted into the pocket 884. The reamer bit 904 canbe inserted through the passage 804 in the offset bushing 838 and theassembly can be dropped onto the distal femur F. The offset bushing 838can then be rotated to the alignment number 842 noted from above. Thefemoral offset template 876 can be secured to the distal femur F. Theoffset bushing 838 can then be removed from the pocket 884. The implantboss reamer bushing 896 can then be inserted into the pocket 884 (FIG.89). The reamer bit 904 can be directed through the implant boss reamerbushing 896 to ream an implant boss 969 (FIGS. 90 and 92).

The implant boss reamer bushing 896 can then be removed from the pocket884 and swapped out for the offset adapter rasp bushing 910. Therotational orientation can be verified (i.e. to match the alignmentnumber noted above). The rasp 922 can be driven (i.e. repeatedly)through the half-moon shaped passage 912 of the offset adapter raspbushing 910 (to create an offset bore portion 970). Again, the offsetadapter rasp bushing 910 aligns the rasp 922 for preparing an offsetpassage within the femoral bore. The offset passage can substantiallycorrespond to the profile (and rotational orientation) of the offsetadapter (see superimposed components, FIG. 93).

If desired, the posterior stabilized box guide 740 (FIGS. 94A and 94B)can be used to create a PS box at the outset of femoral preparation asis known in the art.

An exemplary sequence of preparing a tibia T for accepting a tibialcomponent having an offset adapter will now be described. At the outset,the proximal tibia T can be exposed and resected. A tibial(intramedullary) canal 980 can be reamed using a reamer 956.

Next, the universal revision alignment member 882 can be coupled to topside of the tibial template 890. The offset bushing 838 can be insertedinto the pocket 884 of the universal revision alignment member 882. Thereamer shaft 956 can be inserted through the passage 840 in the offsetbushing 838 and the assembly can be dropped onto the proximal tibia T(FIG. 96). The offset bushing 838 can then be rotated causing the tibialtemplate 890 to translate around the proximal tibia T until optimaltibial coverage is attained. The tibial template 890 is then secured tothe proximal tibia T. The alignment number is noted.

If a proximal augment cut is required, the tibial template 890 withaugment cut block 892 can be secured to the proximal tibia T. Theproximal tibia T can then be cut such as to form a notch 982 (FIG. 98B)on the proximal tibia T. A trial augment 984 can then be inserted ontothe bottom surface of the tibial template 890.

Next, the implant boss reamer bushing 896 can then be inserted into thepocket 884. The tibial bushing stop 900 is then located between thecollar 902 of the reamer bit 904 and the implant boss reamer bushing 896(to limit the depth of cut). The reamer bit 904 can be directed throughthe implant boss reamer bushing 896 to ream the implant boss (FIG. 101).The implant boss reamer bushing 896 and tibial bushing step 900 can thenbe removed from the pocket 884 and swapped out for the offset adapterrasp bushing 910. The rotational orientation can be verified (i.e. tomatch the alignment number noted above). The rasp 922 can be driven(i.e. repeatedly) through the half-moon shaped passage 912 of the offsetadapter rasp bushing 910 to create the offset bore portion. Again, theoffset adapter rasp bushing 910 aligns the rasp 922 for preparing anoffset passage within the tibial bore (FIG. 104). The offset passage cansubstantially correspond to the profile (and rotational orientation) ofthe offset adapter body 604.

With reference to FIG. 105, an apparatus 1000 for aligning an offsetadapter body 604 rotationally with a receiving portion of an implant(i.e. female tapered receiving portion of a tibial component or afemoral component). In the example shown in FIG. 105, the apparatus 1000is shown securing a tibial component 22, while it is appreciated thatthe apparatus can also secure a femoral component (such as any femoralcomponent disclosed herein). The apparatus 1000 can generally define anouter frame 1002 defining a scale of indicia 1004 thereon. A pluralityof arms 1006 can be movably secured to the outer frame 1002. Acorresponding plurality of hands 1010 can be defined on distal ends ofthe arms 1006. Once the plurality of arms 1006 and hands 1010 arepositioned to securably retain the implant (i.e. tray 22), the arms 1006and hands 1010 can be locked in position. In one example, the implant(i.e. tray 22) can be secured in a known position. In the example shown,the known position can be such that the tibial tray 22 is positionedwith the anterior portion aligned with the indicia 1004 (i.e. at indicianumeral “60”). A pointer 1016 can be mounted for rotation around theouter frame 1002.

The indicia 1004 can be at a known location relative to the indicia 842on the offset bushing 838. The pointer can then be rotated around thedial 1004 to correspond to the noted number dialed in with the offsetbushing 838. Next, a mark 1020 (see FIG. 106) can be aligned with thepointer 1016 and dropped into the female tapered receiving portion 30 ofthe tibial tray 22. The Morse-type taper interface, as described indetail, can secure the adapter body 604 relative to the tray 22 untilsupplemental mechanical securement (such as the fastener 90′, FIG. 34,or locking element 606, FIG. 36D).

Another apparatus 1026 for aligning an offset adapter body 604rotationally with a receiving portion of an implant (i.e. female taperedreceiving portion of a tibial component or a femoral component) is shownin FIG. 106. The apparatus 1026 can include the dial 1002, arms 1006 andhands 1010 as described above (or any suitable securing device). A dial1030 can be rotatably suspended above the tibial tray 22. In oneexample, the dial 1030 can rotate within a halo 1032 extending above thedial 1002. The dial 1030 can define a mark 1036 and a keyhole 1040. Thekeyhole can correspond to a footprint that slidably accepts the flats613 of the adapter body 604 so that the adapter body is rotatably fixedin the keyhole 1040. The dial 1030 can be rotated until the mark 1036aligns with the noted number dialed in with the offset bushing 838. Theadapter can then be dropped through the keyhole 1040 and into the femaletapered receiving portion 30 of the tibial tray 22. The Morse-type taperinterface, as described in detail, can secure the adapter body 604relative to the tray 22 until supplemental mechanical securement (suchas the fastener 90′, FIG. 34, or locking element 606, FIG. 36D).

Another apparatus 1040 for aligning an offset adapter body 604rotationally with a receiving portion of an implant (i.e. female taperedreceiving portion of a tibial component or a femoral component) is shownin FIG. 107. The apparatus can include a blister package 1042. Theblister package 1042 can define a pocket 1044 that defines a profilesubstantially corresponding to the footprint of an implant (such as anyfemoral or tibial component described herein). In the example shown, thetibial tray 22 nests in a secure position within the pocket 1044. Adisposable dial 1048 can be loosely provided within the blister package1042. Alternatively, the seal of the blister package or removable topcan act as the dial 1048 and have indicia 1052 printed on the inside ofthe top. The disposable dial 1048 or top can define a perforation 1050and scaled indicia 1052. The disposable dial 1048 can be dropped overthe tapered extension portion of the packaged implant (the inferiorlyextending portion 28 of the tibial tray 22, as shown) such that thetapered extension portion breaks through the perforation 1050. The dial1048 can then be rotated until the mark 1020 aligns with a number of theindicia 1052 that corresponds with the noted number dialed in with theoffset bushing 838. The adapter 604 can then be dropped into the femaletapered receiving portion 30 of the tibial tray 22. The Morse-type taperinterface, as described in detail, can secure the adapter body 604relative to the tray 22 until supplemental mechanical securement (suchas the fastener 90′, FIG. 34, or locking element 606, FIG. 36D).

With reference to FIGS. 108-119, another exemplary method for preparinga tibia during revision surgery will be described. Those skilled in theart will appreciate that with revision surgery, the existing (i.e.,prior implanted) tibial component (e.g. tibial tray, bearing, etc.) isremoved from the tibia. A system or kit of tools 1090 are shown in FIG.108. As illustrated in FIG. 109A, a tibial spacer assembly 1000 isshown. In the depicted example, tibial spacers 1102 a, 1102 b, 1102 c,1102 d, 1102 e, 1102 f, 1102 g, and 1102 h are provided. The tibialspacer 1102 a has a thickness of 10 mm. The remaining tibial spacers1102 b-1102 h each have a thickness of 2 mm. The tibial spacer assembly1100 can be stacked, as needed, to achieve a desired height. Thethickness of a given stack of tibial spacers 1102 a-1102 h (or just thetibial spacer 1102 a used alone) represents a desired thickness of atibial bearing that will be implanted at the proximal tibia. In theexamples provided, the tibial spacer 1102 b can be stacked onto thetibial spacer 1102 a to collectively define a thickness of 12 mm. As canbe appreciated, the tibial spacers 1102 c-1102 h can be sequentiallystacked to achieve additional increments of 2 mm. The tibial spacer 1102c represents (e.g., the cumulative thickness of the tibial spacer 1102c, the tibial spacer 1102 b and the tibial spacer 1102 a) a thickness of14 mm. The tibial spacer 1102 d represents a thickness of 16 mm, and thetibial spacer 1102 e represents a thickness of 18 mm. The tibial spacer1102 f represents a thickness of 20 mm. The spacer 1102 g represents athickness of 22 mm. The spacer 1102 h represents a thickness of 24 mm.In other embodiments, other thicknesses of the assembly 1100 and theindividual spacers 1102 a-1102 h are contemplated. As shown, therespective spacers 1102 a-1102 h can each include a tibial plateauportion, collectively referred to by reference numeral 1104, and ahandle portion, collectively referred to by reference numeral 1106. Eachof the tibial spacers 1102 a-1102 h are rotatably connected at terminalends by way of a fastener 1108. The respective tibial spacers 1102a-1102 h can each pivotally rotate about the fastener 1108 in order toisolate a desired tibial spacer 1102 a-1102 h from the remainder of thespacers 1102 a-1102 h. It is appreciated that while the respectivetibial spacers 1102 a-1102 h are shown attached to each other throughthe fastener 1108, they may alternatively be unattached, separatepieces.

The tibial spacer assembly 1100 can be used to find the joint line of atibia T using anatomical landmarks. More specifically, the tibialplateau portion 1104 of a given tibial spacer 1102 a-1102 h can beplaced atop the tibial plateau of the tibia T or atop the resectedproximal end of the tibia. In other words, the primary tibia is removedand the selected spacer 1102 a-1102 h is positioned on the previouslyresected proximal tibia. In the depicted embodiment, the spacers 1102a-1102 h are universal and can accommodate a left or a right tibia. Theappropriate joint line will be confirmed when the proper thicknessspacer 1102 a-1102 h is placed on the tibial plateau and presents adesired height (i.e., superiorly from the tibial plateau) relative toanatomical landmarks. At this time, a thickness of optional,supplemental augments (i.e., such as those illustrated in FIGS. 55A and55B) can be determined. It is appreciated that it may be necessary toprovide supplemental augments on any combination of the medial andlateral sides of the tibia. The joint line relative to the tibia isknown once the desired thickness of the identified spacer 1102 a-1102 hand the augmentation need is confirmed and noted. The spacer assembly1100 is then removed from the tibia.

Once the joint line has been determined relative to the tibia, anintramedullary (IM) reamer stop 1120 (FIG. 110A) can be coupled to areamer 1122. The reamer 1122 can cooperate with the IM reamer stop 1120to prepare the IM canal of the tibia. During use, the reamer 1122 isable to ream a distance into the IM canal until the reamer stop 1120comes into contact with the proximal tibia.

The IM reamer stop 1120 and the reamer 1122 will now be described ingreater detail with reference to FIGS. 110A and 110B. The IM reamer stop1120 has a superior surface 1126, an inferior surface 1128 and definesan opening 1130 that extends through the IM reamer stop 1120 from thesuperior surface 1126 to the inferior surface 1128. A finger support1132 can be supported on the superior surface 1126 of the IM reamer stop1120. A button 1133 can be coupled to a locating finger 1134. Thelocating finger 1134 can be movably fixed to the finger support 1132. Inone example, the locating finger 1134 can move (e.g., such as bydepression of the button 1133) along an axis that is substantiallytransverse to an axis defined by the reamer 1122. In one example, abiasing member 1136, such as a spring in the depicted embodiment, canbias the locating finger 1134 into engagement with the reamer 1122.

The reamer 1122 can define a reamer shaft 1140 having a plurality ofannular grooves, collectively referred to at reference 1142 formedthereon. As can be appreciated, the grooves 1142 provide a nestinglocation for the locating finger 1134 to control the depth of reamingfor the reamer 1122. According to one example, the grooves 1142 can bemarked with indicia (not specifically shown) that identify variousdepths of reaming for the tibia T (as will become appreciated from thefollowing discussion, the reamer 1122 and the IM reamer stop 1120 canalso be used for preparation of the IM canal in the femur). As such, thegrooves 1142 can also correspond to various depths of reaming in thefemur as well. For exemplary purposes, the grooves 1142 can correspondto 40 mm, 80 mm, 200 mm and other depths of reaming to correspond to adesired stem length. As can be appreciated, the various depths of cutcan correspond to the various lengths of tibial stems, such as thetibial stem 20 illustrated in FIG. 29 or any of the tibial stemsillustrated in FIG. 55A. It is also appreciated in some instances it maybe necessary to implant an offset adapter, such as the offset adapter600 illustrated in FIG. 35 or any of the other offset adapters describedherein, such as the offset adapters illustrated in FIGS. 55A and 55B. Inthose examples wherein an offset adapter is needed in conjunction with astem, the grooves 1142 will correspond to different lengths of stems.For example, if a 40 mm offset adapter will be used, the groove thatcorresponds to an 80 mm tibial stem will also correspond to a 40 mmtibial stem with a 40 mm tibial offset adapter. Those skilled in the artwill appreciate that the dimensions described herein are merelyexemplary. In this way, grooves can be provided in any combination ofconfigurations along the reamer 1122 for identifying a depth of reamingthat can accommodate any combination of stems and/or offset adaptersdescribed herein.

During use, such as the example shown in FIG. 111, various reamers 1122having distinct diameters can be used until adequate cortical contact isachieved in the tibia T. Multiple IM reamer stops 1120 can be provided,each being operatively connected to a reamer 1122 having a distinctdiameter. In this way, a surgeon, when switching to a reamer having abigger diameter, can simply remove the combination of reamer 1122 and IMreamer stop 1120 and utilize another collective set of reamer and IMreamer stop. As can be appreciated, this can minimize the amount of timethat may be required to remove a reamer 1122 from the opening 1130 in anIM reamer stop 1120 and replace it with a reamer having anotherdiameter.

Once the IM canal of the tibia has been sufficiently prepared, as shownin FIG. 111, the IM reamer stop 1120 can be removed from the reamer1122. The reamer 1122 remains in the IM canal. At this point, the reamer1122 is securably retained in a fixed position by the cortical bone ofthe tibia T. Next, as illustrated in FIG. 112A, an IM tibial resectionguide 1144 can be slid over the reamer 1122. The IM tibial resectionguide 1144 can generally comprise a body 1146, an adjustment arm 1148, ablock arm 1150 and a stylus or finger, 1152. The body 1146 can include aresection level adjustment knob 1156. The adjustment arm 1148 includes ahub 1160 that has a passage 1162 formed therethrough. The passage 1162,as shown, can slidably receive the reamer shaft 1140 of the reamer 1122.A coupler 1164 can adjustably secure the adjustment arm 1148 through aslot 1166 formed through the body 1146. The resection block 1170 canthen be secured to the block arm 1150. The resection block 1170 candefine a series of slots 1172 on a medial and lateral side. Inembodiments, a trial stem (not shown) may be inserted into theintramedullary canal in order to act as a positioning reference in placeof the reamer 1122.

The body 1146 can be adjusted along the adjustment arm 1148 to positionthe resection block 1170 against the tibia T. The resection leveladjustment knob 1156 can be rotated to place the resection block 1170 ata desired level (i.e., relative to a proximal surface of the tibia).Once the desired location of the resection block 1170 has been achieved,the resection block 1170 can be fixed to the tibia (such as by pins1174). The remainder of the IM tibial resection guide 1144 along withthe reamer 1122 can be removed.

An exemplary sequence for preparing the proximal tibia for receipt of a5 mm medial augment and a 10 mm lateral augment will now be described.It is appreciated that the medial and lateral cuts can be made toaccommodate any of the tibial augments described herein, such as, butnot limited to augments 540 and 540′ (FIG. 31), augment 540″ (FIG. 32),augment 710 (FIG. 50) or any other of the augments shown in FIGS. 55Aand 55B. The resection level of the IM tibial resection guide 1144 canbe set by rotating the resection level adjustment knob 1156 to thedesired position. In one example, rotation of the resection leveladjustment knob 1156 can adjust the block arm 1150 between a distance of0 and 8 mm along a longitudinal axis of the block arm 1150, which movesthe cutting slots 1172 in the resection block a certain distance fromthe top of the stylus or finger 1152 in the direction of thelongitudinal axis of the block arm 1150. It is appreciated that theresection level adjustment knob 1156 can be configured to adjust theblock arm 1150 to other distances. It is further appreciated that otherIM tibial resection guides may be used. Once the resection level is set,a clean-up cut can be made through the 0 slot of the slots 1172 on themedial side of the resection block 1170. Similarly, a cut can be madethrough the 5 slot of the slots 1172 on the lateral side of theresection block 1170. An exemplary tibia is shown in FIG. 113 aftercutting, while using the resection block 1170. It is appreciated thatthe depths of cut described above are merely exemplary. Those skilled inthe art will appreciate that a depth of cut will be made that isconsistent with the joint line determined as described above that canaccommodate a thickness of a given bearing (i.e., such as any of thebearings discussed herein including 14 (FIG. 1), 214 (FIG. 9), 314 (FIG.15) and 672 (FIG. 42)) and a thickness of a given augment (ifnecessary). Once the proximal tibia has been prepared using theresection block 1170, the resection block 1170 can be removed from thetibia T. The reamer 1122 can then be re-inserted into the IM canal.

With reference now to FIGS. 108 and 114, the offset position of thereamer 1122 will be determined using a tibial offset positioningassembly 1190. The tibial offset positioning assembly 1190 can generallycomprise a tibial template 1192, a tibial alignment member 1194, and aseries of positioning sleeves collectively referred to by reference1196. The tibial template 1192 can generally include a handle portion1200 and a tibial profile portion 1202 (also see FIG. 108). The tibialalignment member 1194 can generally comprise a body 1204 that defines abore 1206 (for rotatably receiving the positioning sleeve 1196) and apair of radial slot passages 1210. The body 1204 can define an alignmentmarker 1212 formed thereon. The positioning sleeves 1196 (FIG. 108) caninclude a neutral positioning sleeve 1198 a (0 offset), an offset sleeve1198 b (2.5 mm offset), an offset sleeve 1198 c (5 mm offset) and anoffset sleeve 1198 d (7.5 mm offset). The positioning sleeves 1196 caneach define a throughbore 1220 a, 1220 b, 1220 c, and 1220 d,respectively that is offset a distance from a longitudinal axis 1222 ofthe positioning sleeves 1196. The positioning sleeves 1196 includeindicia, collectively referenced by numeral 1124. In the example shownin FIG. 114, the offset sleeve 1198 c is received in the bore 1206 ofthe tibial alignment member 1194. The tibial alignment member 1194 canbe fixed to the tibial template 1192 by a locking mechanism 1223.

At this point, it is important to recognize that only the reamer 1122 isfixed relative to the tibia T. The positioning sleeve 1196 is able torotate around its longitudinal axis 1222 causing the tibial alignmentmember 1194 (and the tibial template 1192) to move around the proximaltibia. The positioning sleeve 1196 is rotated (e.g. by the surgeon)around its longitudinal axis 1222 until a position is attained in whichthe tibial profile portion 1200 achieves optimal coverage over theproximal tibia T. In some instances, the surgeon may need to swap outvarious offset sleeves (such as other positioning sleeves 1196) in orderto attain the best possible coverage of the proximal tibia. Once thedesired proximal tibial coverage is verified, the tibial template 1192is fixed relative to the tibia T, such as by pins 1199. At this point,the surgeon can make a note of the indicia 1224 relative to the mark1212 on the tibial alignment member 1194. This will correspond to thetibial offset position. In some instances, no offset will be necessary(i.e., optimal coverage is confirmed with the 0 positioning sleeve 1198a).

Once the tibial template 1192 has been secured to the proximal tibia Twith the pins 1198, the positioning sleeve 1196 can be removed from thealignment member 1194. The reamer 1122 can also be removed at thispoint. One reamer sleeve selected from a group collectively referencedby numeral 1230 (FIG. 108), can then be located into the bore 1206 ofthe tibial alignment member 1194 (FIG. 115). The collective reamersleeves 1230 (FIG. 108) can include a neutral reamer sleeve 1232 a (0 mmoffset, or neutral offset), an offset reamer sleeve 1232 b (2.5 mmoffset), an offset reamer sleeve 1232 c (5 mm offset), and an offsetreamer sleeve 1232 d (7.5 mm offset). The reamer sleeves 1230 can eachdefine a throughbore 1233 a, 1233 b, 1233 c and 1233 d, respectively. Ascan be appreciated, each offset corresponds to a radial offset from thelongitudinal axis of the tibia T. Each of the reamer sleeves 1230 cancorrespond to a respective positioning sleeve 1196. In this way, asurgeon will select an offset reamer sleeve 1230 having a similar offsetas the positioning sleeve 1196 identified above. The reamer sleeves 1230can define indicia 1234 and facets 1235 around its radial surface. Thesurgeon then rotates the offset reamer sleeve 1230 within the bore 1206of the tibial alignment member 1194 to align the indicia 1234 with themark 1212 of the tibial alignment member 1194. It is important torecognize that the surgeon rotates the reamer bushing 1230 in order toalign a common indicia 1234 of the reamer bushing 1230 with the sameindicia 1224 that was determined by the positioning sleeve 1196 (FIG.114). Once the reamer bushing 1230 has been rotated to the desiredorientation, the reamer bushing 1230 can be advanced toward the tibialalignment member 1194 such that the facets 1235 interface with a seriesof flats 1238 (only one flat specifically shown in FIG. 108 formed onthe tibial alignment member 1194).

Turning now to FIGS. 116A and 116B, once the offset reamer sleeve 1230has been rotated to the desired location, a reamer 1240 is insertedthrough the reamer bore (i.e., 1233 c) and an offset cavity 1242 isreamed to accommodate an implant boss (such as the implant boss 28, FIG.34) and an offset adapter (such as the adapter body 604, FIG. 34).Notably, as illustrated in FIG. 116B, the offset reamer sleeve 1230defines an upper plane 1244 and a lower plane 1246 that arenon-parallel. As can be appreciated, the series of offset reamer sleeves1230 can be provided having various upper and lower planes that divergeat various distinct angles. As can be appreciated, each offset reamerbushing (such as 1230) can correspond to an angle of reaming that willaccommodate the profile of any of the given offset adapters (such as theadapter 604, FIG. 35) disclosed herein. As illustrated in FIG. 117, thecavity 1242 can accommodate the adapter body.

In some examples, the neutral offset bushing 1232 a can be used ininstances where an offset adapter is unnecessary. As best shown in FIGS.118A and 118B, the neutral offset bushing 1232 a defines an uppersurface 1252 and a lower surface 1254 that are parallel. A reamer 1260can be used to ream an opening in the proximal tibia that willaccommodate the tibial implant boss (such as reference numeral 28, FIG.35).

In examples where the tibia T must be prepared for receipt of a cruciateaugment (such as augment 450, illustrated in FIG. 60), a cruciateaugment punch 1262 (FIG. 119) can be passed through the bore 1206 of thetibial alignment member 1194. More specifically, the punch 1262 candefine a winged plate with cutting teeth 1264 that can pass through theslot passages 1210 formed on the tibial alignment member 1194 while asurgeon grasps the ribbed handle portion 1266. The surgeon canrepeatedly axially drive the punch 1260 through the tibial alignmentmember 1194 creating the complementary passages in the proximal tibia toreceive the winged portions of the augment 450, as shown in FIG. 120.

With reference now to FIGS. 121-140, another exemplary method forpreparing a femur during revision surgery will be described. Again it isappreciated that in a revision surgery, it may be necessary to remove aprior implanted femoral component in any suitable manner. At the outset,the IM reamer stop 1120 can be coupled to the reamer shaft 1140 at thedesired location. The reamer 1122 can cooperate with the IM reamer stop1120 to prepare the IM canal of the femur in a similar manner asdescribed above with respect to preparation of the IM canal of the tibia(see FIGS. 111 and 112). Also, as discussed above, the grooves 1142 cancorrespond to various depths of reaming into the femur. As can beappreciated, the various depths of reaming can correspond to variouslengths of femoral stems, such as the femoral stem 20 illustrated inFIG. 26 or any of the femoral stems illustrated in FIG. 55A.

As with the tibia, in some instances it may be necessary to implant anoffset adapter, such as the offset adapter 600, FIG. 35 or any of theother offset adapters described herein, such as the adapters illustratedin FIGS. 55A and 55B. In those examples wherein an offset adapter isneeded in conjunction with a stem, the grooves 1142 will correspond todifferent lengths of stems. For example, if a 40 mm offset adapter willbe used, the groove that corresponds to an 80 mm femoral stem (usedalone) will also correspond to a 40 mm femoral stem that will be used inconjunction with a 40 mm femoral offset adapter. Again, the grooves canbe provided in any combination of configurations along the reamer 1122for identifying a depth of reaming that can accommodate any combinationof stems and/or offset adapters described herein. Various reamers 1122having distinct diameters can be used until adequate cortical contact isachieved in the femur F (FIG. 121). As explained above, multiple IMreamer stops 1120 can be provided, each being operatively connected to areamer 1122 having a distinct diameter.

Turning now to FIG. 122A, a femoral spacer 1300 is shown. The femoralspacer 1300 generally comprises a superior surface 1302, an inferiorsurface 1304, a medial surface 1306, a lateral surface 1308 and a boss1310. A medial slot 1314 can be formed along the medial surface 1306. Alateral slot 1316 can be formed along the lateral surface 1308. A seriesof depth markings 1320 can be formed on the boss 1310. The depthmarkings 1320, as will be described, can be referenced to identify anypotential augment requirement on the distal femur. As described above,with reference to FIGS. 26 and 27, in some instances it may be necessaryto implant distal femoral augments, such as identified at referencenumeral 400 and 402, or any other of the augments identified herein,such as the augment 450, FIG. 24, the augment 590, FIG. 33, or any ofthe other augments identified herein, such as illustrated in FIGS. 55Aand 55B.

Once the IM canal has been reamed, the reamer 1122 (along with thereamer stop 1120) can be removed from the femur F. A trial stem 1322with a diameter corresponding to the reamer previously used, can beattached to the boss of the femoral spacer. The boss 1310 of the femoralspacer 1300 in combination with a trial stem can be inserted into the IMcanal of the femur F (FIGS. 122B and 122C). The joint line with respectto the tibia can be re-visualized using one of the same tibial spacers1100 as when preparing the tibia. The tibia T and femur F can then bebrought into extension while keeping the respective femoral spacer 1300and tibial spacer 1100 placed on the femur and tibia, respectively. Thejoint line is represented by the tibial plateau portion 1104 of thetibial spacer 1100, which is determined based on anatomical landmarks.At this time, the distal augmentation needs for the tibia T and femur Fcan be determined by allowing the inferior surface 1304 of the femoralspacer 1300 to meet the tibial plateau portions 1104 of the tibialspacer 1100. Once the two surfaces have met, a number of depth markings1320 may be visible on the medial or lateral side of the femur to implythat a corresponding distal augment may be needed. Likewise, a thicknessof a bearing (such as bearing 14, FIG. 3A or any of the other bearingsidentified herein) can be re-verified. In one example, the femoralspacer 1300 can be adapted for use with either a left or a right femur.The femoral spacer 1300 can be rotated 180 degrees about a boss 1310 foruse between a right or left femur. In other examples, a dedicatedfemoral spacer 1300 can be provided that is specifically configured foreach of a right or left femur.

With reference now to FIG. 123, the femoral spacer 1300 cancooperatively mate with a tower 1326. The tower 1326 can operativelyconnect to a distal revision block 1330. Specifically, the tower 1326can include spacer posts 1332 that can slidably advance along therespective medial and lateral slots 1314 and 1316 defined on the femoralspacer 1300. Block posts 1334 can slidably advance into bores 1338defined in the distal revision block 1330. In one example, the tower1326 and the distal revision block 1330 can be connected to the femoralspacer 1300 while the boss 1310 of the femoral spacer 1300 remains inthe IM canal of the femur F. Once the tower 1326 is advanced into aconnected relationship with the femoral spacer 1300 and the distalrevision block 1330 is advanced into a connected relationship with thetower 1326, the distal revision block 1330 can be secured to the femur Fand the reamer 1122, the tower 1326 and femoral spacer 1300 can beremoved from the femur F (FIG. 124B). Distal cuts can be made on thefemur F using any of the slots 1340 defined in the distal revision block1330 (see FIG. 125) in order to make a distal resection or prepare fordistal augments, if necessary.

With reference now to FIGS. 126A and 126B, a femoral sizer tool 1350 isshown. The femoral sizer tool 1350 can be used to approximate thedesired size of femoral component (i.e., reference number 112, FIG. 8)and/or scaffold, skeleton or frame 1362 (described later herein). Thefemoral sizer tool 1350 can generally include a handle portion 1352, ananterior finger 1354 and a posterior finger 1356. As shown in FIG. 126B,the femoral sizer tool 1350 can be used to approximate theanterior/posterior size of the distal femur F. The femoral sizer tool1350 can be advanced toward the distal femur F, such that the anteriorfinger 1354 and the posterior finger 1356 locate adjacent to therespective posterior and anterior surfaces of the femur F. A pluralityof femoral sizer tools can be provided each having a distinct span Sbetween respective anterior and posterior fingers 1354, 1356. As such,if a selected femoral sizer tool 1350 does not satisfactorily fitagainst an anterior and posterior side of the femur F (see FIG. 126B),another femoral sizer tool having a different span S between respectiveanterior and posterior fingers 1354, 1356 can be used.

Turning now to FIG. 127, a system or kit 1360 having a collection ofcomponents adapted for use in preparing a distal femur according to oneexample of the present teachings is shown. The kit 1360 can include aplurality of different sized scaffold or frames 1362, a mask or femoralalignment member 1364, a cutting block 1366, a posterior stabilized (PS)box guide assembly 1368, a series of locating bushings, collectivelyreferenced by numeral 1370, and a collection of reamer bushings,collectively referenced by numeral 1372. The alignment member 1364 andthe series of locating bushings 1370 and the collection of reamerbushings 1372 can collectively define an alignment assembly. As willbecome appreciated from the following discussion, the kit 1360 of thepresent teachings allows a surgeon to selectively and alternativelyattach, in sequence, the alignment member 1364, the cutting block 1366,and the PS box guide assembly 1368 to the frame 1362. In sum, thealignment member 1364 (in combination with the locating bushing 1370 andthe reamer bushing 1372) can be coupled to the frame 1362 forpreparation of a bore reamed in the distal femur. The alignment member1364 can then be removed from the frame 1362. The cutting block 1366 canthen be coupled to the frame 1362 for preparation of the distal femoralcuts. The cutting block 1366 can then be removed from the frame 1362.The PS box guide assembly 1368 can then be coupled to the frame 1362 andthen necessary cuts for the PS box can then be made in the distal femur.As will become appreciated from the following discussion, by using theframe 1362 as a fixed reference while simply exchanging other componentsof the kit 1360 into the frame 1362, an accurate and efficient system isprovided for preparing the distal femur.

With continued reference to FIG. 127 and additional reference to FIG.128, the frame 1362 and the alignment member 1364 will be described ingreater detail. The frame 1362 can generally comprise an anteriorsection 1380 and a distal section 1382. The distal section 1382 cancomprise a medial frame portion 1384 and a lateral frame portion 1386.The medial frame portion 1384 and the lateral frame portion 1386, alongwith the anterior section 1380, can collectively define an entryway1390. The distal section 1382 can include a first pair of opposingattachment portions or guide slots 1392 formed along the respectivemedial and lateral frame portions 1384 and 1386. The distal section 1382can further comprise a second pair of opposing locking slots 1394 formedalong the medial and lateral frame portions 1384 and 1386. The distalsection 1382 can further comprise cutting surface extensions 1396 formedin the medial and lateral frame portions 1384 and 1386, respectively.The distal section 1382 can further comprise a posterior cutting slot1398. A pair of eyelets 1400 can be formed on the distal section 1382.The anterior section 1380 can define a shelf 1401 and a plurality ofpassages 1402 formed therethrough.

The alignment member 1364 can comprise a body 1404. The body 1404 cangenerally comprise a pair of lateral sections 1406 and an upper section1408. The lateral sections 1406 and the upper section 1408 can cooperateto define a receiving portion or keyway 1410 defined through the body1404. An axial stop 1412 can be formed on the lateral section 1406. Theaxial stop 1412 generally extends into the keyway 1410. A pair oflateral rails 1416 can extend from the respective lateral sections 1406.A locking or transverse rail 1420 can extend from one of the lateralsections 1406. A biasing member 1422 can bias the transverse rail 1420in a direction generally outwardly from the lateral section 1406. Thetransverse rail 1420 can be depressed into a channel 1424 defined in thelateral section 1406 against the bias of the biasing member 1422. A knob1430 can be rotatably fixed to the upper section 1408 of the alignmentmember 1364. The knob 1430 can be operable to rotate about an axis 1432and follow an arcuate path defined by a slot 1434 formed in the uppersection 1408 of the alignment member 1364.

Assembly of the alignment member 1364 into the frame 1362 according toone example of the present teachings will now be described. At theoutset, a surgeon can depress the transverse rail 1420 into the channel1424 of the body 1404. In one example, the transverse rail 1420 can beflush or substantially flush with an outer surface of the lateralsection 1406. Next, the surgeon can advance the alignment member 1364into the entryway 1390 of the frame 1362. More specifically, the lateralrails 1416 of the alignment member 1364 can be aligned with the firstpair of guide slots 1392 of the frame 1362. While the transverse rail1420 remains depressed, the lateral rails 1416 of the alignment member1364 can be advanced along the first pair of guide slots 1392 of theframe 1362. Once the transverse rail 1420 advances to a location beyondthe anterior section 1380, the lateral frame portion 1386 will maintainthe transverse rail 1420 in a depressed position until the transverserail 1420 is aligned with the opposing slot 1394 of the second pair ofopposing slots 1394 formed on the lateral frame portion 1386. Thebiasing member 1422 will then urge the transverse rail 1420 into anested position in the slot 1394 of the second pair of opposing slots.The alignment member 1364 is now secured to the frame 1362. Thealignment member 1364, being secured along two directions (i.e., lateralrail 1416 and transverse rail 1420), provides a secure, robustconnection. It is appreciated that while the first pair of guide slots1392 are shown on the frame 1362 and the lateral and transverse rails1416 and 1420 are shown on the alignment member 1364, they may beprovided on opposite components. In other words, the guide slots 1392can be formed on the alignment member 1364 and the lateral andtransverse rails 1416 and 1420 can be formed on the frame 1362. Otherconfigurations are contemplated.

Referencing now to FIG. 127, the series of locating bushings 1370 willbe described in greater detail. Similar to the positioning sleeves 1196associated with preparation of the tibia above, the series of locatingbushings 1370 can include a neutral locating bushing 1440 a (0 offset or“neutral offset”), an offset locating bushing 1440 b (2.5 mm offset), anoffset locating bushing 1440 c (5 mm offset) and an offset locatingbushing 1440 d (7.5 mm offset). Bores 1450 a, 1450 b, 1450 c and 1450 dcan be formed through each of the locating bushings 1370, respectively.Indicia marks 1452 can be defined around a front face 1454 of each ofthe locating bushings 1370. An annular groove 1456 can be defined arounda circumferential surface 1460 of each of the locating bushings 1370. Alocating bushing 1370 can be selected from the series of locatingbushings 1370 and be advanced into the keyway 1410 of the alignmentmember 1364 until engaging the axial stop 1412. The axial stop 1412 canpreclude the locating bushing 1370 from advancing further axially. Next,the knob 1430 can be rotated from the position shown in FIG. 130 to aposition shown in FIG. 131. By rotating the knob 1430 around the axis1432, a scalloped shaft 1462 can extend into the keyway 1410 andtherefore into a nested position in the annular groove 1456 formedaround the circumferential wall 1460 of the locating bushing 1370,whereas prior to rotating the knob 1430 the scallop of the shaft waspositioned to allow the diameter of the locating bushing to pass by.With the knob 1430 rotated in the locked position as shown in FIG. 131,the shaft 1462 will preclude withdrawal of the locating bushing 1370from the keyway 1410. The locating bushing 1370 is still permitted torotate around its axis 1451 within the keyway 1410.

Next, a posterior foot 1470 will be described in greater detail. Theposterior foot 1470 can generally comprise a handle portion 1472, a finportion 1474 and a catch 1476. The posterior foot 1470 can beselectively coupled to the frame 1362 as illustrated in FIGS. 131 and132. Specifically, in one example, the catch 1476 (FIG. 127) can beinserted into the posterior foot slot 1398 of the distal section 1382 onthe frame 1362. The posterior foot 1470 can be used along with the tibiaspacers 1100 to match the flexion gap as illustrated in FIG. 132 (i.e.,the tibia and femur positioned in flexion) to the extension gap (thetibia and femur positioned in extension as described above with respectto FIGS. 122B and 122C). It will be appreciated that it may be necessaryto change the frame 1362 to a different sized frame if the discrepancybetween flexion and extension gaps is unsatisfactory or similarly to usea different size offset or different offset position.

With the reamer 1122 extending through the offset bore 1450 of thelocating bushing 1370, the locating bushing 1370 can be rotated (e.g.,by the surgeon) around its longitudinal axis 1451 (FIG. 129) until aposition is attained in which the frame 1362 achieves optimal coverageover the distal femur. In one example, while rotating the locatingbushing 1370, the surgeon can refer to the position of the posteriorfoot 1470 and the tibia spacer 1100 as reference (FIG. 133). In someinstances, the frame 1362 can occupy a position on the distal femur thatsatisfies adequate bone coverage, but the flexion gap does not match theextension gap. In this case, it may be necessary to change the femoralsize (change the frame 1362 to a different sized frame). It isappreciated that it may be necessary to swap out locating bushings 1370until a locating bushing 1370 having an offset (or a neutral offset)that corresponds to the best distal femoral coverage is achieved.

Once optimal coverage of the distal femur is attained and the flexiongap and the extension gap are matched, the frame 1362 can be secured inplace relative to the distal femur. In one example, pins or fasteners1480 can be inserted through the eyelets 1400 defined on the frame 1362.Again, it is important to note that once the frame 1362 is sufficientlysecured to the distal femur, the other components of the kit 1360 (thealignment member 1364, the cutting block 1366, and the PS box guideassembly 1368) can all be switched out while the frame 1362 remainsfixed to the distal femur. Those skilled in the art will appreciate thatby using the frame 1362 as a fixed reference, accuracy can be improvedduring formation of the offset bore, the cuts, and the PS box cuts.Likewise, it is appreciated that by providing a common reference point(the frame 1362), a surgeon may require less time to accomplishpreparation of the distal femur.

A surgeon then makes a note of the indicia mark 1452 that is alignedwith the alignment indicator 1425 of the alignment member 1364. Next,the locating bushing 1370 is removed from the alignment member 1364(FIG. 134). To remove the locating bushing 1370 from the alignmentmember 1364 a surgeon can rotate the knob 1430 around the axis 1432 intothe unlocked position (FIG. 134). The locating bushing 1370 can then bewithdrawn from the keyway 1410. The reamer 1122 can also be removedthrough the keyway 1410. In some examples, it may be necessary to removethe alignment member 1364 from the frame 1362 prior to withdrawal of thereamer 1120 from the keyway 1410. In such an example, a surgeon cansimply depress the transverse rail 1420 into the channel 1424 and removethe alignment member 1364 by sliding the lateral rails 1416 from thefirst pair of guide slots 1392 defined in the frame 1362.

Next, a reamer bushing 1372 can be inserted into the keyway 1410 of thealignment member 1364. Returning now to FIG. 127, the reamer bushings1372 can include a neutral reamer bushing 1520 a (0 mm offset or“neutral offset”), an offset reamer bushing 1520 b (2.5 mm offset), anoffset reamer bushing 1520 c (5 mm offset) and an offset reamer bushing1520 d (7.5 mm offset). A front face 1524 of each of the reamer bushing1372 includes indicia marks 1522, respectively. An annular groove 1530can be defined around a circumferential surface 1532 of each of thereamer bushings 1372. Offset bores 1536 a, 1536 b, 1536 c and 1536 d canbe formed through each of the reamer bushings 1372, respectively. Facets1538 can be formed on each of the reamer bushings 1372. The reamerbushings 1372 each define a longitudinal axis 1540. The selected reamerbushing 1372 can be advanced into the keyway 1410 of the alignmentmember 1364 until engaging the front face 1404 (the reamer bushings havea ledge to stop them from moving further axially. The angled surfacesinterface with the facets on the reamer bushings to lock the reamerbushings in the desired position.

The surgeon then rotates the reamer bushing 1372 within the keyway 1410of the alignment member 1364 to align the indicia marks 1522 with thenoted indicia mark 1452 that was aligned with the alignment indicator1425 above. The reamer bushing 1372 can then be advanced further intothe keyway 1410 to the position shown in FIG. 136A. The knob 1430 canthen be rotated along its axis 1432 causing the shaft 1462 to nest intothe annular groove 1530 defined around the circumferential surface 1532.As with the locating bushing 1370 described above, the shaft 1462 canpreclude withdrawal of the reamer bushing 1372 from the keyway 1410. Thereamer bushing 1372 cannot rotate because it locks into place when thefacets 1538 interface with 3 flats/axial stops formed on the alignmentmember 1364. As can be appreciated, each of the reamer bushings 1372correspond to a respective locating bushing 1370. In this way, a surgeonwill select a reamer bushing 1372 having a similar offset as thelocating bushing 1370 identified above. As shown in FIG. 136B, theoffset reamer bushing 1520 d defines a first plane 1560 and a secondplane 1562 that are non-parallel. As can be appreciated, the series ofreamer bushings 1372 can be provided having various first and secondplanes that diverge at various distinct angles. As can be appreciated,each reamer bushing 1372 can correspond to an angle of reaming that willaccommodate the profile of any of the given offset adapters (such as theadapter 604, FIG. 41A) disclosed herein. In some examples, a neutralreamer bushing 1520 a can be used in instances where an offset adapteris unnecessary.

A reamer 1570 can be used to ream an opening in the distal femur thatwill accommodate the femoral implant boss (such as reference numeral130, illustrated in FIG. 8) as well as an offset adapter such as 604 ifnecessary. The reamer 1570 is guided by the offset bore 1536 of thereamer bushing 1372.

The alignment member 1364 is then removed from the frame 1362. In orderto remove the alignment member 1364 from the frame 1362, in one example,a surgeon can depress the transverse rail 1420 such that it withdrawsfrom the second opposing slot 1394. The alignment member 1364 can thenbe withdrawn from the entryway 1390 by traversing the lateral rails 1416of the alignment member 1364 along the first pair of guide slots 1392 ofthe frame 1362.

Next, the cutting block 1366 is coupled to the frame 1362. Again, it isappreciated that the frame 1362 remains fixed to the distal femur. Thecutting block 1366 attaches to the frame 1362 in the same manner asdescribed above with respect to the alignment member 1364. The cuttingblock 1366 includes lateral rails 1602 (FIG. 127) and transverse rails1604. In one example, such as the one shown in FIGS. 137 a and 137 b,transverse rails 1604 can be included on opposite lateral sides of thecutting block. The transverse rails 1604 can each be biased by a biasingmember 1606 in a direction generally outwardly from the cutting block1366. The transverse rails 1604 can be depressed into respectivechannels 1610 against the bias of the biasing member 1606 of the cuttingblock 1366. The cutting block 1366 can further define a plurality oftool guides 1614 formed thereon. The tool guides 1614 can be configuredto guide a blade of a bone saw.

In one example, according to the present teachings, a surgeon candepress the transverse rails 1604 into the respective channels 1610 ofthe cutting block 1366. The transverse rails 1604 can be flush orsubstantially flush with an outer surface of the cutting block 1366.Next, the surgeon can advance the cutting block 1366 into the entryway1390 of the frame 1362. More specifically, the lateral rails 1602 of thecutting block 1366 can be aligned with the first pair of guide slots1392 of the frame 1362. While the transverse rails 1604 remaindepressed, the lateral rails 1602 of the cutting block 1366 can beadvanced along the first pair of guide slots 1392 of the frame 1362.Once the transverse rails 1604 advance to a location beyond an outersurface of the frame 1362, the transverse rails 1604 will remain in adepressed position until they are aligned with the second pair ofopposing slots 1394 formed on the lateral frame portion 1386 of theframe 1362. The biasing members 1606 will then urge the respectivetransverse rails 1604 into a nested position in the respective opposingslots 1394. The cutting block 1366 is now secured to the frame 1362.Next, a surgeon can perform the cuts, such as chamfer cuts, posterioraugment cuts through the tool guides 1614 in a manner known in the art.An anterior surface cut can also be performed on the femur. Theposterior cut may be made through the posterior cutting slot in theframe 1362.

Once the distal femur has been prepared with the cutting block 1366, thecutting block 1366 can be removed from the frame 1362. To remove thecutting block 1366 from the frame 1362 according to one example of thepresent teachings, the transverse rails 1604 can be depressed into theirrespective channels 1610. The cutting block 1366 can then be withdrawnfrom the frame 1362 by sliding the lateral rails 1602 from the firstpair of guide slots 1392 defined in the frame 1362.

Next, referring to FIGS. 138 and 139, the PS box guide assembly 1368 iscoupled to the frame 1362. Again, it is appreciated that the frame 1362remains fixed to the distal femur. The PS box guide assembly 1368 cangenerally comprise a first PS box guide component 1360 and a second PSbox guide component 1632. The first PS box guide component 1360 cangenerally comprise a U-shaped body 1636 having rails 1640 defined alongits lateral sides. The second PS box guide component 1632 can generallycomprise a C-shaped body 1644. The C-shaped body 1644 can defineretaining slots 1648 and a catch 1650. In one example, the second PS boxguide component 1632 can be located against the anterior section 1380 ofthe frame 1362, such that the catch 1650 locates onto the shelf 1401 ofthe anterior section 1380. The rails 1640 of the first PS box guidecomponent 1630 can then slidably locate through the retaining slot 1648of the second PS box guide component 1632 and the first pair of guideslots 1392 of the frame 1362. The PS box can then be resected in amanner known in the art. Next, the PS box guide assembly 1368 can beremoved from the frame 1362 and the frame 1362 can be removed from thedistal femur. Trial components can then be used to trial the distalfemur in a manner known in the art. As shown in FIG. 140, a femoralcomponent 112 having a femoral boss 130, offset adapter 604 and stem 20,such as described herein, can then be implanted onto the distal femur F.

While the above discussion has been generally directed towardinstrumentation and a method for performing revision knee surgery, aprimary knee replacement surgery can be similarly performed. One methodfor preparing a tibia during primary knee replacement surgery accordingto one example of the present teachings will now be described in greaterdetail.

At the outset, an IM canal can be reamed with a starter reamer in thetibia as is known in the art. The reamer 1122 can then be used with thereamer stop 1120, as discussed above, to ream the IM canal of the tibiauntil adequate cortical bone is contacted. It should be noted that theproximal tibia shall be resected using an IM tibial resection guideassembly. The remainder of the procedure for preparing a tibia for aprimary knee replacement surgery is substantially similar to theprocedure described above with respect to preparation of a tibia duringa revision procedure.

One method for preparing a femur during primary knee replacement surgeryaccording to one example of the present teachings will now be describedin greater detail. At the outset, an IM canal can be reamed with astarter reamer in the femur as is known in the art. Next, with referenceto FIG. 141, an AP sizer 1660 can be used to determine theanterior/posterior size of the distal femur. Other tools may be used todetermine the anterior/posterior size of the femur.

Next, a distal resection guide, such as guide 800 FIG. 61 can be used toperform distal and/or augment cuts (i.e. such as at 5 degrees), seeFIGS. 82 and 83. The reamer 1122 can then be used with the reamer stop1120 as discussed above to ream the IM canal of the femur until adequatecortical bone is contacted. It will be appreciated for a primary femoralprocedure, the distal resection will decrease the depth of the initialream.

With reference now to FIG. 142, an anterior final cutter 1700 can beused to make the final anterior cut on the distal femur. The anteriorfinal cutter can include body 1702, a central block 1704, a knob 1706, aknuckle 1708 and a finger 1710. The central block 1704 can define a pairof overlapping bores 1714 that correspond to a right and left femur. Arespective bore 1714 can receive the reamer shaft 1140. A slot 1718 canbe formed in the body 1702 for receiving a cutter during cutting of theanterior femur. During use, the anterior final cutter 1700 can beadvanced over the reamer shaft 1140 (e.g. through the identified bore).The knob 1706 can then be rotated causing the body 1702 to move in theanterior/posterior direction relative to the central block 1704. Oncethe femoral size corresponds to that determined by the AP sizer, thebody 1702 is pinned in place by pins 1722 on the distal femur. Theanterior final cut can then be made through the slot 1718. As can beappreciated, the anterior section 1380 of the frame can reference theanterior final cut on the distal femur.

The remainder of the procedure for preparing a femur for a primary kneereplacement surgery is substantially similar to described above withrespect to preparation of a femur during a revision procedure.

While the disclosure has been described in the specification andillustrated in the drawings with reference to a preferred embodiment, itwill be understood by those skilled in the art that various changes maybe made and equivalents may be substituted for elements thereof withoutdeparting from the scope of the disclosure as defined in the claims. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the disclosure without departing fromthe essential scope thereof. Therefore, it is intended that thedisclosure not be limited to the particular embodiment illustrated bythe drawings and described in the specification as the best modepresently contemplated for carrying out this disclosure, but that thedisclosure will include any embodiments falling within the descriptionof the appended claims.

What is claimed is:
 1. A method for preparing at least a first bone forreceiving a prosthesis, the method comprising: positioning anintramedullary (IM) member in a bone; locating a frame onto the bone ata desired location; coupling an alignment assembly to the frame, thealignment assembly comprising an alignment member and a locatingbushing, the alignment member having a receiving portion; moving thealignment assembly relative to the IM member to position the frame at adesired location relative to the bone wherein moving the alignmentassembly comprises: positioning the locating bushing into the receivingportion, the locating bushing defining a bore configured to accept theIM member therethrough; and rotating the locating bushing within thereceiving portion until the frame locates at the desired locationrelative to the bone; fixing the frame to the bone at the desiredlocation; removing the locating bushing from the alignment member andthe IM member from the bone; inserting a reamer bushing into thereceiving portion of the alignment member; reaming a cavity into thebone using the reamer bushing as a guide; removing the alignmentassembly from the frame; coupling a cutting block to the frame; andpreparing cuts on the bone using the cutting block as a guide.
 2. Themethod of claim 1, further comprising: removing the cutting block fromthe frame; coupling a posterior stabilized (PS) box guide assembly tothe frame; and preparing PS box cuts on the bone using the PS box guideassembly as a guide.
 3. The method of claim 1, further comprising:coupling a posterior foot to the frame; and locating a joint lineassociated with the bone by referencing a position of the posteriorfoot.
 4. The method of claim 1, further comprising: identifying a firstindicia mark on the locating bushing relative to a mark on the alignmentmember once the desired location is reached; and rotating the reamerbushing within the receiving portion until a second indicia mark on thereamer bushing aligns with the mark on the alignment member, wherein thefirst and second indicia marks correspond to each other.
 5. The methodof claim 1, further comprising: selecting the locating bushing from aplurality of locating bushings each having a bore that is offset fromthe longitudinal axis of the bushing a distinct distance; and selectingthe reaming bushing from a plurality of reaming bushings each having areaming bore that is offset a distance that corresponds to the bores ofthe locating bushings.
 6. The method of claim 1, wherein inserting areamer bushing into the receiving portion further comprises: moving anengaging portion provided on the alignment member from a disengagedposition to an engaged position, the engaging portion nesting in anannular groove formed around the reaming bushing in the engaged positionsubstantially inhibiting movement of the bushing along the longitudinalaxis while permitting rotation of the reaming bushing around thelongitudinal axis.
 7. The method of claim 6 wherein moving the engagingportion from a disengaged position to an engaged position comprises:rotating a knob coupled to afoot, wherein rotation of the knob causesthe foot to move from a position generally away from engagement with theannular groove to a position generally nested into the annular groove ofthe reamer bushing.
 8. The method of claim 1 wherein coupling thealignment assembly to the frame comprises: depressing a rail associatedwith one of the frame or the alignment assembly; and slidably advancingthe rail along a guide slot defined on the other of the frame or thealignment assembly; and slidably advancing the rail along a guide slotdefined on the other of the frame or the alignment assembly until therail retracts from the depressed position and located into a lockingslot coupling the alignment assembly to the frame.
 9. The method ofclaim 1, further comprising: removing a previously implanted prosthesisfrom the bone; and implanting a revision prosthesis into the bone. 10.The method of claim 1 wherein positioning the IM member includes reamingthe bone with a reamer until cortical bone contact is achieved.
 11. Themethod of claim 1, further comprising: coupling a posterior foot to theframe; confirming the position of the bone relative to a second bonewhile the bone and second bone are in a first orientation; and fixingthe frame to the bone at the desired location once a desired position ofthe bone and second bone in the first orientation is confirmed.
 12. Themethod of claim 1, further comprising: preparing a second bone forreceiving a prosthesis, wherein the bone is a femur and the second boneis a tibia.
 13. A method for preparing at least a first bone forreceiving a prosthesis, the method comprising: positioning anintramedullary (IM) member in a first bone; locating a frame having afirst attachment portion and a second attachment portion onto the firstbone; coupling an alignment assembly to the first attachment portion,the alignment assembly including an alignment member and a locatingbushing, the alignment member having a receiving portion; moving thealignment assembly relative to the IM member to position the frame at adesired location relative to the first bone, wherein moving thealignment assembly comprises: positioning the locating bushing into thereceiving portion, the locating bushing defining a bore configured toaccept the IM member therethrough; and rotating the locating bushingwithin the receiving portion until the frame locates at the desiredlocation relative to the first bone; coupling a posterior foot to thesecond attachment portion, confirming a position of the first bonerelative to a second bone while the first and second bones are in afirst orientation while referencing the posterior foot; fixing the frameto the first bone at the desired location once a desired position of thefirst and second bones in the first orientation is confirmed; removingthe locating bushing from the alignment member; removing the IM memberfrom the first bone; inserting a reamer bushing into the receivingportion of the alignment member; and reaming a cavity into the firstbone using the reamer bushing as a guide.
 14. The method of claim 13,further comprising: selecting the frame from a plurality of frameshaving different sizes; and selecting another frame from the pluralityof frames if the desired location cannot be attained.
 15. The method ofclaim 13 wherein the first bone is a femur and the second bone is atibia and wherein the first orientation is defined when the femur andtibia are in flexion.
 16. The method of claim 15 wherein confirming theposition of the first bone relative to the second bone further compriseslocating a tibial spacer onto a proximal end of the tibia while theposterior foot is located along a posterior side of the femur and in aposition generally opposed to the tibial spacer.
 17. The method of claim16, further comprising: positioning a femoral spacer relative to adistal femur; and confirming a position of the femur relative to thetibia while the femur and the tibia are in extension while referencingthe femoral spacer and the tibial spacer.
 18. The method of claim 13,further comprising: removing a previously implanted prosthesis from thebone.
 19. The method of claim 13 wherein positioning the IM memberincludes reaming the bone with a reamer until cortical bone contact isachieved.
 20. The method of claim 13, further comprising: removing thealignment assembly from the frame; coupling a cutting block to the firstattachment portion; and preparing cuts on the first bone using thecutting block as a guide.
 21. The method of claim 20, furthercomprising: removing the cutting block from the frame; coupling aposterior stabilized (PS) box guide assembly to the first attachmentportion; and preparing PS box cuts on the first bone using the PS boxguide assembly as a guide.
 22. The method of claim 13, furthercomprising: identifying a first indicia mark on the locating bushingrelative to a mark on the alignment member once the desired location isreached; and rotating the reamer bushing within the receiving portionuntil a second indicia mark on the reamer bushing aligns with the markon the alignment member, wherein the first and second indicia markscorrespond to each other.
 23. The method of claim 22, furthercomprising: selecting the locating bushing from a plurality of locatingbushings each having a bore that is offset from the longitudinal axis ofthe bushing a distinct distance; and selecting the reaming bushing froma plurality of reaming bushings each having a reaming bore that isoffset a distance that corresponds to the bores of the locatingbushings.
 24. A method for preparing at least a first bone for receivinga prosthesis, the method comprising: positioning an intramedullary (IM)member in a bone; locating a frame onto the bone at a desired location;coupling an alignment assembly to the frame wherein the couplingcomprises: depressing a rail associated with one of the frame or thealignment assembly; slidably advancing the rail along a guide slotdefined on the other of the frame or the alignment assembly until therail retracts from the depressed position and locates into a lockingslot in the other of the frame or the alignment assembly; moving thealignment assembly relative to the IM member to position the frame at adesired location relative to the bone; fixing the frame to the bone atthe desired location; reaming a cavity into the bone using at least aportion of the alignment assembly as a guide; removing the alignmentassembly from the frame; coupling a cutting block to the frame; andpreparing cuts on the bone using the cutting block as a guide.
 25. Themethod of claim 24 wherein moving the alignment assembly comprises:positioning a locating bushing into a receiving portion of the alignmentassembly, the locating bushing defining a bore configured to accept theIM member therethrough; and rotating the locating bushing within thereceiving portion until the frame locates at the desired locationrelative to the bone.
 26. The method of claim 25, further comprising:removing the locating bushing from the receiving portion; inserting areamer bushing into the receiving portion; moving an engaging portionprovided on the alignment assembly from a disengaged position to anengaged position, the engaging portion nesting in an annular grooveformed around the reaming bushing in the engaged position substantiallyinhibiting movement of the reaming bushing along a longitudinal axiswhile permitting rotation of the reaming bushing around the longitudinalaxis.
 27. The method of claim 26 wherein moving the engaging portionfrom a disengaged position to an engaged position comprises: rotating a(nob coupled to a foot, wherein rotation of the knob causes the foot tomove from a position generally away from engagement with the annulargroove to a position generally nested into the annular groove of thereamer bushing.